Gotway buzzer flag.

[enaon]

I think I found the buzzer on gotways, it is pending testing to check if it goes hi on the 80% condition.

Do some tests if you have some time, I think it is important to be implemented as soon as possible if it works.

https://forum.electricunicycle.org/topic/22393-vibrator-engine/page/2/?tab=comments#comment-369013
https://www.youtube.com/watch?v=sdHYzd1EY68