Update to latest FAIKIN version

[jf2020]

First of all I really would like to thank you @ddv2005 and @revk for contributing this fantastic project. The hardware design and the software are very nice and I could order 10 pcs for $75 including shipping to Europe.

The software in this repo is a bit old and I needed the latest version from @revk to get support for the Mi BLE sensors. I considered making a PR, but it was easier to just compile the software directly from https://github.com/revk/ESP32-Faikin.

If someone wants to do the same, change the GPIOs to use in Faikin.c

#define	gpio	
	io(tx,26)	
	io(rx,27)
	led(blink,3,-18 -19 -5)
#endif

and use the wroom target make wroom.