Support the ESP8266_RTOS_SDK (WPA3 for the ESP8266)

[Mat931]

Describe the problem you have/What new integration you would like

• The ESP8266_NONOS_SDK (which is used by ESP8266 Arduino) no longer receives feature updates (starting from December 2019). [Source]
• New features like WPA3 and PMF are only supported by the ESP8266_RTOS_SDK.

Please describe your use case for this integration and alternatives you've tried:

• I would like to enable WPA3 and PMF for my WiFi network. Currently there are no alternatives.
• I hope the RTOS SDK will also improve the connection issues on all my ESP8266 devices.

Additional context

• Discussion about migrating the Arduino framework to the ESP8266_RTOS_SDK: Migrate core from NONOS SDK to FreeRTOS SDK esp8266/Arduino#5790
• Espressif is planning to migrate the ESP8266_RTOS_SDK to esp-idf [1] [2]
• WPA3 #605

[benedikt-bartscher]

Thanks @Mat931 for pointing to the new SDK. Maybe this saves me from opening all my wall switches (about 40) and spending a lot of money.
Currently i run a seperate wifi only for esphome with esp8266, but its less secure and blocks wifi channels.