Change the usbd_*_report() family of functions to take a usbd_device

Change the usbd_*_report() family of functions to take a usbd_device
and a infaceno argument instead of an iface pointer.  While here,
remove some unused functions and inlined usbd_read_report_desc since
it is used only once.

This is part of plumbing required to convert the various USB HID devices
to handle multiples report IDs.

ok andre@