* Reduce the number of supported HID reports of IDs per descriptor.
This saves ~200 bytes in the default HID objects.
* (Not enabled) Compute QSTR attrs on init. This trades 1k RAM for
flash. Flash is the default (1).
This started while adding USB MIDI support (and descriptor support is
in this change.) When seeing that I'd have to implement the MIDI class
logic twice, once for atmel-samd and once for nrf, I decided to refactor
the USB stack so its shared across ports. This has led to a number of
changes that remove items from the ports folder and move them into
supervisor.
Furthermore, we had external SPI flash support for nrf pending so I
factored out the connection between the usb stack and the flash API as
well. This PR also includes the QSPI support for nRF.
Reece Robinson
Scott Shawcroft
Dan Halbert
microDev
Yihui Xiong