[SCSI] qla4xxx: check for failed conn setup

iscsi_conn_setup can fail so we must check for NULL being
returned.
Signed-off-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

drivers/scsi/qla4xxx/ql4_os.c

@@ -1207,6 +1207,9 @@ qla4xxx_conn_create(struct iscsi_cls_session *cls_sess, uint32_t conn_idx)
 	DEBUG2(printk(KERN_INFO "Func: %s\n", __func__));
 	cls_conn = iscsi_conn_setup(cls_sess, sizeof(struct qla_conn),
 				    conn_idx);
+	if (!cls_conn)
+		return NULL;
+
 	sess = cls_sess->dd_data;
 	ddb_entry = sess->dd_data;
 	ddb_entry->conn = cls_conn;