esp32: fix some WiFi bugs

Fix following WiFi bugs:
1. Make smartconfig thread-safe
2. Fix WiFi stop/deinit memory leak
3. Refactor for WiFi init/deinit/ioctl etc
4. Add declaration for esp_wifi_internal_ioctl()
5. Fix the bug that WiFi stop leads to task watchdog

components/esp32/include/esp_wifi.h

@@ -1102,6 +1102,19 @@ esp_err_t esp_wifi_set_ant(const wifi_ant_config_t *config);
   */
 esp_err_t esp_wifi_get_ant(wifi_ant_config_t *config);
 
+/**
+  * @brief     A general API to set/get WiFi internal configuration, it's for debug only
+  *
+  * @param     cmd : ioctl command type
+  * @param     cfg : configuration for the command
+  *
+  * @return
+  *    - ESP_OK: succeed
+  *    - others: failed
+  */
+esp_err_t esp_wifi_internal_ioctl(int cmd, wifi_ioctl_config_t *cfg);
+
+
 #ifdef __cplusplus
 }
 #endif