Xiaomi R3G v1: No internet after update

[pavelgl]

@Betuterien

config device
        option name 'wan'
        option macaddr '00:xx:xx:xx:xx:9F'

This is the correct setting. Remove the rest.

There was a similar case some time ago. Try connecting an unmanaged switch between the wan interface and the ISP (as an eventual unverified workaround), or downgrade to version 19.07.10.