Cross-merge networking fixes after downstream PR.

No conflicts (sort of) and no adjacent changes.

This merge reverts commit b3c9e65e ("net: hsr: remove seqnr_lock")
from net, as it was superseded by
commit 430d67bd ("net: hsr: Use the seqnr lock for frames received via interlink port.")
in net-next.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>