scsi: libfc: Fix array index out of bound exception

Fix array index out of bound exception in fc_rport_prli_resp().

Link: https://lore.kernel.org/r/20210615165939.24327-1-jhasan@marvell.com
Signed-off-by: Javed Hasan <jhasan@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>