Allow stalling non-0-length control OUT transfers

[xairy]

This issue is caused by a limitation of the USB Gadget API.

Right now, all UDC drivers auto-complete the status stage of non-0-length control OUT transfers. As a result, it's impossible to stall such transfers. There was a patch series that intended to address this, but it was never merged. See the discussion for more details.

To resolve this, we would need to extend the Gadget API, add support into all/relevant UDC drivers, and then extend the Raw Gadget UAPI interface.