LU-13043 quota: remove annoying message in osd_declare_inode_qid()

LU-13043 quota: remove annoying message in osd_declare_inode_qid()

The admin shouldn't be getting console error messages when a user goes
over quota(this would be happening continuously at some sites).

In some call paths, the "*flags" parameter may be NULL, don't try to
access it in that case.

As a general cleanup, move the QUOTA_FL_* flags over to a named enum
"enum osd_quota_local_flags" so that it is easier to see what this field
actually holds, rather than a totally generic "int *flags" argument that
has to be hunted through the code.

Lustre-change: https://review.whamcloud.com/36906
Lustre-commit: b3005155317b27e19c8029e6a9f92e69d0dd905e

Fixes: d30f9e6b6c5d ("LU-11425 quota: support quota for DoM")
Change-Id: Id5686ecdb8a943e48a2888067e321f83b8569188
Signed-off-by: Wang Shilong <wshilong@ddn.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Hongchao Zhang <hongchao@whamcloud.com>
Reviewed-by: Stephan Thiell <sthiell@stanford.edu>
Signed-off-by: Minh Diep <mdiep@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/37131
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>