LU-13394 llite: avoid sending OST RPC for project setting

LU-13394 llite: avoid sending OST RPC for project setting

LL_IOC_FSSETXATTR ioctl could be used to handle inode flags
setting, currently it is mainly used to hanlde project ID changing.

The only flags for project is inherit flag, there is no need
to send this to OST, so we could avoid this kind of RPC to OSS.

Change-Id: Ief97959216be807d5efe936eba368d5262a521b0
Signed-off-by: Wang Shilong <wshilong@ddn.com>
Reviewed-on: https://review.whamcloud.com/38089
Tested-by: jenkins <devops@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Li Xi <lixi@ddn.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>