qcacld-3.0: Fix mem leak in wma_data_tx_ack_work_handler()

Mem leak in tx ack work handler.

Free allocated memory in wma_data_tx_ack_work_handler()

Change-Id: Id79072902ac43a60998624429872a2a489cecbf1
CRs-Fixed: 2828030

core/wma/src/wma_data.c

@@ -913,6 +913,7 @@ static void wma_data_tx_ack_work_handler(void *ack_work)
 
 	if (cds_is_load_or_unload_in_progress()) {
 		wma_err("Driver load/unload in progress");
+		qdf_mem_free(ack_work);
 		return;
 	}