esp_wifi: wifi support new event mechanism

1. WiFi support new event mechanism
2. Update examples to use new event mechanism

examples/protocols/http_server/advanced_tests/main/main.c

@@ -8,7 +8,7 @@
 */
 
 #include "esp_wifi.h"
-#include "esp_event_loop.h"
+#include "esp_event.h"
 #include "esp_log.h"
 #include "esp_system.h"
 #include "nvs_flash.h"

examples/protocols/http_server/file_serving/main/main.c

@@ -10,7 +10,7 @@
 #include <sys/param.h>
 
 #include "esp_wifi.h"
-#include "esp_event_loop.h"
+#include "esp_event.h"
 #include "esp_log.h"
 #include "esp_system.h"
 #include "esp_spiffs.h"

examples/protocols/http_server/persistent_sockets/main/main.c

@@ -8,7 +8,7 @@
 */
 
 #include <esp_wifi.h>
-#include <esp_event_loop.h>
+#include <esp_event.h>
 #include <esp_log.h>
 #include <esp_system.h>
 #include <nvs_flash.h>

examples/protocols/http_server/restful_server/main/esp_rest_main.c

@@ -6,7 +6,6 @@
    software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
    CONDITIONS OF ANY KIND, either express or implied.
 */
-#include "esp_event_loop.h"
 #include "driver/sdmmc_host.h"
 #include "driver/gpio.h"
 #include "esp_vfs_semihost.h"