scsi: sd_zbc: Fix sd_zbc_complete()

The ILLEGAL REQUEST/INVALID FIELD IN CDB error generated by an attempt to
reset a conventional zone does not apply to the reset write pointer command
with the ALL bit set, that is, to REQ_OP_ZONE_RESET_ALL requests. Fix
sd_zbc_complete() to be quiet only in the case of REQ_OP_ZONE_RESET,
excluding REQ_OP_ZONE_RESET_ALL.

Since REQ_OP_ZONE_RESET is the only request handled by sd_zbc_complete(),
also simplify the code using a simple if statement.

[mkp: applied by hand]

Fixes: d81e9d49

 ("scsi: implement REQ_OP_ZONE_RESET_ALL")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20191027140549.26272-4-damien.lemoal@wdc.com
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>