scsi: ibmvfc: fix misdefined reserved field in ibmvfc_fcp_rsp_info

The fcp_rsp_info structure as defined in the FC spec has an initial 3
bytes reserved field. The ibmvfc driver mistakenly defined this field as
4 bytes resulting in the rsp_code field being defined in what should be
the start of the second reserved field and thus always being reported as
zero by the driver.

Ideally, we should wire ibmvfc up with libfc for the sake of code
deduplication, and ease of maintaining standardized structures in a
single place. However, for now simply fixup the definition in ibmvfc for
backporting to distros on older kernels. Wiring up with libfc will be
done in a followup patch.

Cc: <stable@vger.kernel.org>
Reported-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>