esp_wifi: fix WiFi scan and connect bugs when coexist with Bluetooth

1. Fix WiFi scan leads to poor performance of Bluetooth.
2. Improve WiFi connect success ratio when coexist with Bluetooth.
3. Check if WiFi is still connected when CSA or beacon timeout happen.
4. add coex pre init

components/esp32/cpu_start.c

@@ -423,6 +423,7 @@ void start_cpu0_default(void)
 
 #if CONFIG_ESP32_WIFI_SW_COEXIST_ENABLE
     esp_coex_adapter_register(&g_coex_adapter_funcs);
+    coex_pre_init();
 #endif
 
     bootloader_flash_update_id();