[SCSI] fcoe: make it possible to verify fcoe with sparse

Analyzing fcoe with sparse currently fails. This is because struct
fcoe_rcv_info contains two enum members that have been declared with
__attribute__((packed)). Apparently gcc honors this attribute while sparse
ignores it. The result is that sizeof(struct fcoe_rcv_info)
== sizeof(struct sk_buff::cb) == 48 on a 64-bit system according to gcc, but
not according to sparse. The patch below modifies the definition of
struct fcoe_rcv_info such that gcc and sparse interpret this structure
definition in the same way. The current sparse output is as follows:

$ cd linux-2.6.34
$ make C=2 M=drivers/scsi/fcoe modules
 CHECK   drivers/scsi/fcoe/fcoe.c

include/scsi/fc_frame.h:81:9: error: invalid bitfield width, -1.
 CC [M]  drivers/scsi/fcoe/fcoe.o
 CHECK   drivers/scsi/fcoe/libfcoe.c

include/scsi/fc_frame.h:81:9: error: invalid bitfield width, -1.
drivers/scsi/fcoe/libfcoe.c:56:37: error: invalid initializer

Signed-off-by: Bart Van Assche <bart.vanassche@gmail.com>
Cc: jeykholt@cisco.com
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>