Merge branch 'net-mctp-improvements-for-null-eid-addressing'

Jeremy Kerr says:

====================
net: mctp: improvements for NULL-EID addressing

Currently, our focus for the MCTP routing implementation has been for
MCTP bus-owner devices. In this case, we will generally have an EID
assigned during local transmit, and have routes established before
expecting to receive.

We also want to handle non-bus-owner cases, where:

 - we may need to send control protocol messages (like Discovery Notify)
   before any local addresses have been assigned, particularly as part
   of acquiring a local address assignment; and

 - we will likely want to receive incoming messages before we have
   routing established.

This series improves handling for these cases, by handling NULL EIDs
as source / destination addresses where possible.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
====================

Link: https://patch.msgid.link/20260331-dev-mctp-null-eids-v1-0-b4d047372eaf@codeconstruct.com.au
Signed-off-by: Paolo Abeni <pabeni@redhat.com>