Merge branch 'mctp-add-mctp-over-usb-hardware-transport-binding'

Jeremy Kerr says:

====================
mctp: Add MCTP-over-USB hardware transport binding

Add an implementation of the DMTF standard DSP0283, providing an MCTP
channel over high-speed USB.

This is a fairly trivial first implementation, in that we only submit
one tx and one rx URB at a time. We do accept multi-packet transfers,
but do not yet generate them on transmit.

Of course, questions and comments are most welcome, particularly on the
USB interfaces.

v2: https://lore.kernel.org/20250212-dev-mctp-usb-v2-0-76e67025d764@codeconstruct.com.au
v1: https://lore.kernel.org/20250206-dev-mctp-usb-v1-0-81453fe26a61@codeconstruct.com.au
====================

Link: https://patch.msgid.link/20250221-dev-mctp-usb-v3-0-3353030fe9cc@codeconstruct.com.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>