LU-11623 mdt: return UPDATE|PERM on open

LU-11623 mdt: return UPDATE|PERM on open

This patch includes the following changes:
* try lock UPDATE|PERM ibits on open to speed up subsequent stat.
* open returns PR lock to client by default, because CR mode
  UPDATE|PERM ibits don't make sense since all modifications take
  PW lock.
* don't lock UPDATE|PERM ibits for PCC attach, otherwise these ibits
  revoke will cause file detach.
* update sanity-pcc 13a to make it fail on single client test if
  anything went wrong.
* update sanity-lfsck 31d because previously CR UPDATE lock is
  fetched, thus the test pass by mistake.

This should help common workloads with open followed by a stat
or other such operation.

Benchmark results:

This patch can significantly improve open-create + stat on the same
client.

This patch in combination with two others:

https://review.whamcloud.com/32157
https://review.whamcloud.com/33584

Improves the 'stat' side of open-create + stat by >10x.

Without patches (master branch commit 26a7abe):

mpirun -np 24 --allow-run-as-root /work/tools/bin/mdtest -n 50000 -d
/cache1/out/ -F -C -T -v -w 32k

   Operation                      Max            Min           Mean
   ---------                      ---            ---           ----
   File creation     :       3838.205       3838.204       3838.204
   File stat         :      33459.289      33459.249      33459.271
   File read         :          0.000          0.000          0.000
   File removal      :          0.000          0.000          0.000
   Tree creation     :       3146.841       3146.841       3146.841
   Tree removal      :          0.000          0.000          0.000

With the three patches:

mpirun -np 24 --allow-run-as-root /work/tools/bin/mdtest -n 50000 -d
/cache1/out/ -F -C -T -v -w 32k
SUMMARY rate: (of 1 iterations)
   Operation                      Max            Min           Mean
   ---------                      ---            ---           ----
   File creation     :       3822.440       3822.439       3822.440
   File stat         :     350620.140     350615.980     350617.193
   File read         :          0.000          0.000          0.000
   File removal      :          0.000          0.000          0.000
   Tree creation     :       2076.727       2076.727       2076.727
   Tree removal      :          0.000          0.000          0.000

Note 33K stats/second vs 350K stats/second.

ls -l time of the mdtest directory is also reduced from 23.5 seconds
to 5.8 seconds.

Change-Id: Ib3410629c190de6f74246a4a92f8216537fa2b95
Signed-off-by: Oleg Drokin <green@whamcloud.com>
Signed-off-by: Lai Siyao <lai.siyao@whamcloud.com>
Signed-off-by: Qian Yingjiin <qian@ddn.com>
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/33585
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Tested-by: Shuichi Ihara <sihara@ddn.com>
Reviewed-by: Mikhail Pershin <mpershin@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>