scsi: 3w-sas: Remove unneeded variable 'retval'

Fix the following coccicheck warning:

 ./drivers/scsi/3w-sas.c:866:5-11: Unneeded variable: "retval". Return "1"
on line 898

Link: https://lore.kernel.org/r/1615272064-42109-1-git-send-email-yang.lee@linux.alibaba.com


Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>