qcacld-3.0: Add vdev_mlme NULL check in lim_get_self_dot11_mode()

Handle the possibility of NULL value for VDEV MLME component in
lim_get_self_dot11_mode().

Change-Id: I43ba34f0f1de53961c0f3ad2e675ddae899360d8
CRs-Fixed: 3356646

core/mac/src/pe/lim/lim_process_sme_req_messages.c

@@ -1922,6 +1922,11 @@ lim_get_self_dot11_mode(struct mac_context *mac_ctx, enum QDF_OPMODE opmode,
 		return self_dot11_mode;
 
 	vdev_mlme = wlan_vdev_mlme_get_cmpt_obj(vdev);
+	if (!vdev_mlme) {
+		wlan_objmgr_vdev_release_ref(vdev, WLAN_MLME_OBJMGR_ID);
+		return self_dot11_mode;
+	}
+
 	vdev_dot11_mode = vdev_mlme->proto.vdev_dot11_mode;
 	wlan_objmgr_vdev_release_ref(vdev, WLAN_MLME_OBJMGR_ID);