Add support for sonoff s-mate and r5 (ewelink-remote sub-devices)

I recommend supporting the sonoff Bluetooth devices (s-mate and r5) to be integrated via Bluetooth that belongs to the Raspberry Pi or any local Home Assistant server. Also, this support should be added to esphome so we can add those Bluetooth (LE) devices to the sonoff devices that support ewelink remote control or any esp32 device.

They don’t seem to use the standard Bluetooth protocol, but a proprietary protocol called eWeLink-Remote

Yea, it’s a Bluetooth (LE) ibeacon