scsi: zfcp: use endianness conversions with common FC(P) struct fields

Just to silence sparse. Since zfcp only exists for s390 and
s390 is big endian, this has been working correctly without conversions
and all the new conversions are NOPs so no performance impact.

Nonetheless, use the conversion on the constant expression where possible.

NB: N_Port-IDs have always been handled with hton24 or ntoh24 conversions
because they also convert to / from character array.

Affected common code structs and .fields are:

HOT I/O PATH:
fcp_cmnd .fc_dl
   FCP command: regular SCSI I/O, including DIX case

SEMI-HOT I/O PATH:
fcp_cmnd .fc_dl
   recovery FCP command: task management function (LUN / target reset)
fcp_resp_ext
   FCP response having FCP_SNS_LEN_VAL with .fr_rsp_len .fr_sns_len
   FCP response having FCP_RESID_UNDER with .fr_resid

RECOVERY / DISCOVERY PATHS:
fc_ct_hdr .ct_cmd .ct_mr_size
   zfcp auto port scan [GPN_FT] with fc_gpn_ft_resp.fp_wwpn,
   recovery for returned port [GID_PN] with fc_ns_gid_pn.fn_wwpn,
   get symbolic port name [GSPN],
   register symbolic port name [RSPN] (NPIV only).
fc_els_rscn .rscn_plen
   incoming ELS (RSCN).
fc_els_flogi .fl_wwpn .fl_wwnn
   incoming ELS (PLOGI),
   port open response with .fl_csp.sp_bb_data .fl_cssp[0..3].cp_class,
   FCP channel physical port,
   point-to-point peer (P2P only).
fc_els_logo .fl_n_port_wwn
   incoming ELS (LOGO).
fc_els_adisc .adisc_wwnn .adisc_wwpn
   path test after RSCN for gone target port.

Since v4.10 commit 05de9700

 ("linux/types.h: enable endian checks for
all sparse builds"), below sparse endianness reports appear by default.
Previously, one needed to pass argument CF="-D__CHECK_ENDIAN__" to make
as in: $ make C=1 CF="-D__CHECK_ENDIAN__" M=drivers/s390/scsi.

Silenced sparse warnings and one error:

$ make C=1 M=drivers/s390/scsi
...
  CHECK   drivers/s390/scsi/zfcp_dbf.c
drivers/s390/scsi/zfcp_dbf.c:463:22: warning: restricted __be16 degrades to integer
drivers/s390/scsi/zfcp_dbf.c:476:28: warning: restricted __be16 degrades to integer
  CC      drivers/s390/scsi/zfcp_dbf.o
...
  CHECK   drivers/s390/scsi/zfcp_fc.c
drivers/s390/scsi/zfcp_fc.c:263:26: warning: restricted __be16 degrades to integer
drivers/s390/scsi/zfcp_fc.c:299:41: warning: incorrect type in argument 2 (different base types)
drivers/s390/scsi/zfcp_fc.c:299:41:    expected unsigned long long [unsigned] [usertype] wwpn
drivers/s390/scsi/zfcp_fc.c:299:41:    got restricted __be64 [usertype] fl_wwpn
drivers/s390/scsi/zfcp_fc.c:309:40: warning: incorrect type in argument 2 (different base types)
drivers/s390/scsi/zfcp_fc.c:309:40:    expected unsigned long long [unsigned] [usertype] wwpn
drivers/s390/scsi/zfcp_fc.c:309:40:    got restricted __be64 [usertype] fl_n_port_wwn
drivers/s390/scsi/zfcp_fc.c:338:31: warning: restricted __be16 degrades to integer
drivers/s390/scsi/zfcp_fc.c:355:24: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fc.c:355:24:    expected restricted __be16 [usertype] ct_cmd
drivers/s390/scsi/zfcp_fc.c:355:24:    got unsigned short [unsigned] [usertype] cmd
drivers/s390/scsi/zfcp_fc.c:356:28: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fc.c:356:28:    expected restricted __be16 [usertype] ct_mr_size
drivers/s390/scsi/zfcp_fc.c:356:28:    got int
drivers/s390/scsi/zfcp_fc.c:379:36: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fc.c:379:36:    expected restricted __be64 [usertype] fn_wwpn
drivers/s390/scsi/zfcp_fc.c:379:36:    got unsigned long long [unsigned] [usertype] wwpn
drivers/s390/scsi/zfcp_fc.c:463:18: warning: restricted __be64 degrades to integer
drivers/s390/scsi/zfcp_fc.c:465:17: warning: cast from restricted __be64
drivers/s390/scsi/zfcp_fc.c:473:20: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fc.c:473:20:    expected unsigned long long [unsigned] [usertype] wwnn
drivers/s390/scsi/zfcp_fc.c:473:20:    got restricted __be64 [usertype] fl_wwnn
drivers/s390/scsi/zfcp_fc.c:474:29: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fc.c:474:29:    expected unsigned int [unsigned] [usertype] maxframe_size
drivers/s390/scsi/zfcp_fc.c:474:29:    got restricted __be16 [usertype] sp_bb_data
drivers/s390/scsi/zfcp_fc.c:476:30: warning: restricted __be16 degrades to integer
drivers/s390/scsi/zfcp_fc.c:478:30: warning: restricted __be16 degrades to integer
drivers/s390/scsi/zfcp_fc.c:480:30: warning: restricted __be16 degrades to integer
drivers/s390/scsi/zfcp_fc.c:482:30: warning: restricted __be16 degrades to integer
drivers/s390/scsi/zfcp_fc.c:500:28: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fc.c:500:28:    expected unsigned long long [unsigned] [usertype] wwnn
drivers/s390/scsi/zfcp_fc.c:500:28:    got restricted __be64 [usertype] adisc_wwnn
drivers/s390/scsi/zfcp_fc.c:502:38: warning: restricted __be64 degrades to integer
drivers/s390/scsi/zfcp_fc.c:541:40: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fc.c:541:40:    expected restricted __be64 [usertype] adisc_wwpn
drivers/s390/scsi/zfcp_fc.c:541:40:    got unsigned long long [unsigned] [usertype] port_name
drivers/s390/scsi/zfcp_fc.c:542:40: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fc.c:542:40:    expected restricted __be64 [usertype] adisc_wwnn
drivers/s390/scsi/zfcp_fc.c:542:40:    got unsigned long long [unsigned] [usertype] node_name
drivers/s390/scsi/zfcp_fc.c:669:16: warning: restricted __be16 degrades to integer
drivers/s390/scsi/zfcp_fc.c:696:24: warning: restricted __be64 degrades to integer
drivers/s390/scsi/zfcp_fc.c:699:54: warning: incorrect type in argument 2 (different base types)
drivers/s390/scsi/zfcp_fc.c:699:54:    expected unsigned long long [unsigned] [usertype] <noident>
drivers/s390/scsi/zfcp_fc.c:699:54:    got restricted __be64 [usertype] fp_wwpn
  CC      drivers/s390/scsi/zfcp_fc.o
  CHECK   drivers/s390/scsi/zfcp_fsf.c
drivers/s390/scsi/zfcp_fsf.c:479:34: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fsf.c:479:34:    expected unsigned long long [unsigned] [usertype] port_name
drivers/s390/scsi/zfcp_fsf.c:479:34:    got restricted __be64 [usertype] fl_wwpn
drivers/s390/scsi/zfcp_fsf.c:480:34: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fsf.c:480:34:    expected unsigned long long [unsigned] [usertype] node_name
drivers/s390/scsi/zfcp_fsf.c:480:34:    got restricted __be64 [usertype] fl_wwnn
drivers/s390/scsi/zfcp_fsf.c:506:36: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fsf.c:506:36:    expected unsigned long long [unsigned] [usertype] peer_wwpn
drivers/s390/scsi/zfcp_fsf.c:506:36:    got restricted __be64 [usertype] fl_wwpn
drivers/s390/scsi/zfcp_fsf.c:507:36: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fsf.c:507:36:    expected unsigned long long [unsigned] [usertype] peer_wwnn
drivers/s390/scsi/zfcp_fsf.c:507:36:    got restricted __be64 [usertype] fl_wwnn
drivers/s390/scsi/zfcp_fc.h:269:46: warning: restricted __be32 degrades to integer
drivers/s390/scsi/zfcp_fc.h:270:29: error: incompatible types in comparison expression (different base types)

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>