LU-8399 osp: direct reference object to be invalidate

LU-8399 osp: direct reference object to be invalidate

If the cross-MDTs update failed, the OSP transcation callback
will invalidate related object(s) cache. Originally, it uses
lu_object_find() to locate the object by FID. But it may be
blocked if related object is marked as dying (for some reason,
such as purged when umount).

To avoid such trouble, we make the "osp_update_request" to
reference related object(s) directly, then when needs to
invalidate, we can access the object(s) directly without
locating again.

Test-Parameters: alwaysuploadlogs mdsfilesystemtype=ldiskfs mdtfilesystemtype=ldiskfs ostfilesystemtype=ldiskfs mdscount=2 mdtcount=4 testlist=sanity-scrub,sanity-scrub,sanity-scrub
Signed-off-by: Fan Yong <fan.yong@intel.com>
Change-Id: I043182b349b38153cce4e20b2675556ead94c6c1
Reviewed-on: http://review.whamcloud.com/21330
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: wangdi <di.wang@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>