Merge branch 'improve-tsn_lib-selftests-for-future-distributed-tasks'

Vladimir Oltean says:

====================
Improve tsn_lib selftests for future distributed tasks

Some of the boards I am working with are limited in the number of ports
that they offer, and as more TSN related selftests are added, it is
important to be able to distribute the work among multiple boards.
A large part of implementing that is ensuring network-wide
synchronization, but also permitting more streams of data to flow
through the network. There is the more important aspect of also
coordinating the timing characteristics of those streams, and that is
also something that is tackled, although not in this modest patch set.
The goal here is not to introduce new selftests yet, but just to lay a
better foundation for them. These patches are a part of the cleanup work
I've done while working on selftests for frame preemption. They are
regression-tested with psfp.sh.
====================

Link: https://lore.kernel.org/r/20220923210016.3406301-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>