qcacld-3.0: Add null check in wma_hold_req_timer

mac pointer that is a result of func "cds_get_context"
that may return null.

Add null check for mac pointer while sending the connect rsp.

Change-Id: I51c021b99b2014fafc4c33519b0de6dbeffa0025
CRs-Fixed: 3120707

core/wma/src/wma_dev_if.c

@@ -3476,6 +3476,10 @@ void wma_hold_req_timer(void *data)
 			wma_trigger_recovery_assert_on_fw_timeout(
 				WMA_DELETE_STA_REQ,
 				QDF_PEER_DELETION_TIMEDOUT);
+		if (!mac) {
+			wma_err("mac: Null Pointer Error");
+			goto timer_destroy;
+		}
 		lim_cm_send_connect_rsp(mac, NULL, tgt_req->user_data,
 					CM_GENERIC_FAILURE,
 					QDF_STATUS_E_FAILURE, 0, false);