futex: fixup wait_lock/pi_lock locking rule changes

The v4.4 version of "Add the rtmutex rework" needs to be updated due
to the futex backports from v4.4.280. The fixes are needed due the
locking rules change (hb->lock and mutex->wait_lock).

This fixup is based on the 0283ca853c78 ("Add the rtmutex rework") and
on what is in v4.9.280-rt186.

Signed-off-by: Daniel Wagner <wagi@monom.org>
2 files changed