LU-15491 mdt: rename lock inversion deadlock

LU-15491 mdt: rename lock inversion deadlock

MDT rewrite got rid of lock ordering by fid and replaced it
with parent/child ordering, but child to child lock inversion is
still possible with hardlinks as follows:

thread 1: mv dir1/10 dir2/10
thread 2: mv dir2/11 dir2/2
where dir1/10 is hardlink to dir4/2 and dir2/10 is hardlink to dir2/11

To solve this we enforce child ordering by fid in case of local rename

This should not create problems aynwhere else but rename since
the next closest candidate - link() does not delete the target
if it exists so it's not locked in that case.

Fixes: d76cc65d5d68 ("LU-12125 mds: allow parallel regular file rename")
Change-Id: Idd3525e8b1a0de411766bdcaa480c60d3b5e491b
Signed-off-by: Oleg Drokin <green@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/46352
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Hongchao Zhang <hongchao@whamcloud.com>