temporarily work around for fixing eth2ap

Closes https://github.com/espressif/esp-idf/issues/3726
Closes https://github.com/espressif/esp-idf/issues/3728

examples/ethernet/eth2ap/README.md

@@ -1,6 +1,8 @@
 # eth2ap Example
 (See the README.md file in the upper level 'examples' directory for more information about examples. To try a more complex application about Ethernet to WiFi data forwarding, please go to [iot-solution](https://github.com/espressif/esp-iot-solution/tree/master/examples/eth2wifi).)
 
+**Note:** This example uses some internal APIs (e.g. `esp_wifi_internal_tx`) which might get changed between minor versions of ESP-IDF.
+
 ## Overview
 ![eth2ap](eth2ap.png)
 

examples/ethernet/eth2ap/main/ethernet_example_main.c

@@ -192,7 +192,8 @@ static void initialize_wifi(void)
 {
     ESP_ERROR_CHECK(esp_event_handler_register(WIFI_EVENT, ESP_EVENT_ANY_ID, wifi_event_handler, NULL));
     wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
-    ESP_ERROR_CHECK(esp_wifi_init_internal(&cfg));
+    ESP_ERROR_CHECK(esp_wifi_init(&cfg));
+    ESP_ERROR_CHECK(tcpip_adapter_clear_default_wifi_handlers());
     ESP_ERROR_CHECK(esp_wifi_set_storage(WIFI_STORAGE_RAM));
     wifi_config_t wifi_config = {
         .ap = {