Revert "LU-7782 scrub: handle slave obj of striped directory"

Revert "LU-7782 scrub: handle slave obj of striped directory"

This seems to be causing frequent failures documented in
LU-8399.

This reverts commit 80fe81c5b14835bbd5d751e878edbd00fe90f797.

Test-Parameters: trivial testlist=sanity-scrub,sanity-scrub,sanity-scrub,sanity-scrub,sanity-scrub,sanity-scrub

Change-Id: I84077375673e52244117d98ef4d76a36a4333ad8
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Reviewed-on: http://review.whamcloud.com/21313
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: James Nunez <james.a.nunez@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>