scsi: pmcraid: Remove set but not used 'res'

This addresses the following gcc warning with "make W=1":

 drivers/scsi/pmcraid.c: In function ‘pmcraid_abort_cmd’:
 drivers/scsi/pmcraid.c:2863:33: warning: variable ‘res’ set but not
 used [-Wunused-but-set-variable]
   struct pmcraid_resource_entry *res;
                                    ^

Link: https://lore.kernel.org/r/20200909082627.101984-2-yebin10@huawei.comReported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Ye Bin <yebin10@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/pmcraid.c

@@ -2860,10 +2860,8 @@ static struct pmcraid_cmd *pmcraid_abort_cmd(struct pmcraid_cmd *cmd)
 {
 	struct pmcraid_cmd *cancel_cmd;
 	struct pmcraid_instance *pinstance;
-	struct pmcraid_resource_entry *res;
 
 	pinstance = (struct pmcraid_instance *)cmd->drv_inst;
-	res = cmd->scsi_cmd->device->hostdata;
 
 	cancel_cmd = pmcraid_get_free_cmd(pinstance);