wifi: Map esp_wifi_init() to esp_wifi_init_internal()

Follow-on patches will include additional functionality in
esp_wifi_init()

components/esp32/event_default_handlers.c

@@ -408,3 +408,8 @@ esp_err_t esp_event_process_default(system_event_t *event)
     }
     return ESP_OK;
 }
+
+esp_err_t esp_wifi_init(wifi_init_config_t *config)
+{
+     return esp_wifi_init_internal(config);
+}

components/esp32/include/esp_wifi_internal.h

@@ -40,6 +40,20 @@
 extern "C" {
 #endif
 
+/**
+ * @brief Initialize Wi-Fi Driver
+ *     Alloc resource for WiFi driver, such as WiFi control structure, RX/TX buffer,
+ *     WiFi NVS structure among others.
+ *
+ * @param  config provide WiFi init configuration
+ *
+ * @return
+ *    - ESP_OK: succeed
+ *    - ESP_ERR_WIFI_NO_MEM: out of memory
+ *    - others: refer to error code esp_err.h
+ */
+esp_err_t esp_wifi_init_internal(wifi_init_config_t *config);
+
 /**
   * @brief  get whether the wifi driver is allowed to transmit data or not
   *