LU-14847 ptlrpc: two replay lock threads

LU-14847 ptlrpc: two replay lock threads

conflict to each other what leads to:
        ASSERTION( atomic_read(&imp->imp_replay_inflight) == 1 )

replay_lock_interpret() does ptlrpc_connect_import() on error, and one
thread will appear starting with connect reply interpret.

replay_lock_interpret() also wakes up ldlm_lock_replay_thread() which
does ptlrpc_import_recovery_state_machine().

It may happen that both threads will get to ldlm_replay_locks() on the
next round at the same time, both increment imp_replay_inflight and
the second one will assert.

The problem appeared in LU-13600 which added ldlm_lock_replay_thread()
with the ptlrpc_import_recovery_state_machine() call.

HPE-bug-id: LUS-10147
Fixes: 3b613a442b ("LU-13600 ptlrpc: limit rate of lock replays")
Signed-off-by: Vitaly Fertman <vitaly.fertman@hpe.com>
Change-Id: Ia9aafb631e3ba5f850504cc58b4826acec2813bd
Reviewed-by: Andriy Skulysh <andriy.skulysh@hpe.com>
Reviewed-by: Alexander Zarochentsev <alexander.zarochentsev@hpe.com>
Reviewed-on: https://es-gerrit.dev.cray.com/158931
Tested-by: Jenkins Build User <nssreleng@cray.com>
Reviewed-on: https://review.whamcloud.com/44294
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Mike Pershin <mpershin@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>