fanLevelControl stays at 0 when adjusted
I've been using one of your other plugin "homebridge-xiaomi-fan" which works great except that I can't stop/oscillate the fan in Control Center. But, I found out that this "homebridge-miot" can do that; a feature I sorely missed cause I often access devices through Control Center in iOS.

However, there's only one issue with it - it consistently reports zero speed when adjusting the fanLevelControl. Tried this on zhimi.fan.za4 (Smartmi Standing Fan 2S). My other Xiaomi fans like zhimi.fan.fb1 (Mi Smart Air Circulator Fan) and dmaker.fan.p9 (Mi Smart Tower Fan) doesn't exhibit this issue though.

Also, is it possible to change to other fan icon in HomeKit? I don't see that option, but my ceiling fan connected to wall switch does show three different fan icons.

![IMG_B2DA92C8B745-1](https://user-images.githubusercontent.com/66505845/128934554-be43436c-a220-4610-9504-992974ee505b.jpeg)

Appreciate your response. Thank you!
