scsi: lpfc: remove an unnecessary NULL check

Smatch complains about this code:

    drivers/scsi/lpfc/lpfc_scsi.c:1053 lpfc_get_scsi_buf_s4()
    warn: variable dereferenced before check 'lpfc_cmd' (see line 1039)

Fortunately the NULL check isn't required so I have removed it.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/lpfc/lpfc_scsi.c

@@ -1050,7 +1050,7 @@ lpfc_get_scsi_buf_s4(struct lpfc_hba *phba, struct lpfc_nodelist *ndlp)
 	if (!found)
 		return NULL;
 
-	if (lpfc_ndlp_check_qdepth(phba, ndlp) && lpfc_cmd) {
+	if (lpfc_ndlp_check_qdepth(phba, ndlp)) {
 		atomic_inc(&ndlp->cmd_pending);
 		lpfc_cmd->flags |= LPFC_SBUF_BUMP_QDEPTH;
 	}