LU-12017 ldlm: DoM truncate deadlock

LU-12017 ldlm: DoM truncate deadlock

setxattr takes inode lock and sends reint to MDS.
truncate takes MDS_INODELOCK_DOM lock and wants
to acquire inode lock.

MDS locks are for different bits
MDS_INODELOCK_UPDATE|MDS_INODELOCK_XATTR vs
MDS_INODELOCK_DOM but they blocks each other if
some blocking lock was present earlier.

If IBITS waiting lock has no conflicts with any lock in the
granted queue or any lock ahead in the waiting queue then
it can be granted.

Use separate waiting lists for each ibit to eliminate full
lr_waiting list scan.

Lustre-change: https://review.whamcloud.com/35057
Lustre-commit: 2250e072c37855d611aa64027945981fe2c8f4d7

Cray-bug-id: LUS-6970
Change-Id: I95b2ed0b1a0063b7ece5277a5ee06e2511d44e5f
Signed-off-by: Andriy Skulysh <c17819@cray.com>
Reviewed-by: Mike Pershin <mpershin@whamcloud.com>
Reviewed-by: Patrick Farrell <pfarrell@whamcloud.com>
Signed-off-by: Minh Diep <mdiep@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/35937
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Stephan Thiell <sthiell@stanford.edu>
Reviewed-by: Oleg Drokin <green@whamcloud.com>