LU-11678 quota: protect quota flags at OSC

LU-11678 quota: protect quota flags at OSC

There is no protection in OSC quota hash tracking the quota flags of
different qid, which could cause the previous request to modify the
quota flags which was set by the current request because the replies
could be out of order.

This patch also adds a lock to protect the operations on the quota
hash from different requests.

Test-Parameters: testlist=sanity-quota,sanity-quota,sanity-quota,sanity-quota

Lustre-change: https://review.whamcloud.com/33747
Lustre-commit: 77d9f4e05a5c366ad0f7c2e97a338c6958676f73

Change-Id: Ia6e5141265beacb9401dd533081fa0b85fd5ea6a
Signed-off-by: Hongchao Zhang <hongchao@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Wang Shilong <wshilong@ddn.com>
Signed-off-by: Minh Diep <mdiep@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/34915
Tested-by: Jenkins
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>