- Allows classes to handle vendor requests.
- Allows classes to use a single handler for multiple interfaces.
- Allows classes to access the other events (previously only `reset` was available).
This brings it inline with the other embassy-usb descriptor APIs and allows it to integrate well with the Builder to allow class constructors to add MS OS descriptors.
Also adds a `usb_serial_winusb` example to demonstrate how to use the API.
1151: USB: allow setting the interface string for interface alt settings r=Dirbaio a=mattico
This is a breaking change to embassy-usb's API.
Co-authored-by: Matt Ickstadt <matt@beckenterprises.com>
The stack reads its own descriptors to figure out which endpoints
are used in which alt settings, and enables/disables them as needed.
The ControlHandler has a callback so it can get notified of alternate
setting changes, which is purely informative (it doesn't have to do anything).
The same API call allocates interfaces/endpoints/etc and writes their descriptors.
This means less API calls, and less possibility to screw things up.
DescriptorWriter is now private.
