Greetings developers and contributors.

For ESP32 boards XTAL_FREQ_AUTO can be set using sdkconfig so that single firmware can be used with different crystal frequencies, Where as for ESP8266 boards such configuration is not available and is left to the flashing tool to patch the header for correct flashing mode, flashing frequency.

This causes issue with flashing tools such as esp-web-tools which doesn't patch the header and expects correct XTAL frequency to be set in the firmware(NabuCasa/esp-web-flasher#103 (comment)).