Merge branch 'mptcp-misc-fixes-for-v7-1-rc2'

Matthieu Baerts says:

====================
mptcp: misc fixes for v7.1-rc2

Here are various unrelated fixes:

- Patches 1-2: set timestamp flags on 'ssk', not 'sk' (typo); Plus do
  that with sleepable lock_sock/release_sock. A fix for v5.14.

- Patch 3: respect SO_LINGER(1, 0) by sending MP_FASTCLOSE at close time
  as expected. A fix for v6.1.

- Patch 4: reset fullmesh counter after a flush. A fix for v6.19.
====================

Link: https://patch.msgid.link/20260427-net-mptcp-misc-fixes-7-1-rc2-v1-0-7432b7f279fa@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>