657: Async usb stack r=Dirbaio a=Dirbaio
TODO
- [x] Make it work on nRF
- [x] Add a way for classes to handle their own EP0 control requests - thanks `@alexmoon!`
- [x] Handle CONTROL OUT requests with data.
- [ ] Impl AsyncRead/AsyncWrite for CDC ACM -- will do later, it's not trivial
- [x] Cleanup unwraps/asserts/panics
- [x] Cleanup logs (make everything trace/debug, not info)
- [ ] Port synopsys-usb-otg
- [ ] Port stm32-usbd
- [ ] Add more classes? HID, MSD?
Co-authored-by: Dario Nieuwenhuis <dirbaio@dirbaio.net>
Co-authored-by: alexmoon <alex.r.moon@gmail.com>