LU-6317 lfsck: NOT count the objects repeatedly

LU-6317 lfsck: NOT count the objects repeatedly

The namespace LFSCK uses object-table based iteration plus namespace
based directory traversing to scan the system. So one object will be
returned twice by them. Counting the objects repeatedly will confuse
the users. So the namespace LFSCK should only count the objects that
are scanned via namespace based directory traversing.

Signed-off-by: Fan Yong <fan.yong@intel.com>
Change-Id: I36459743843e1db1e9372d46d3aafddef033d699
Reviewed-on: http://review.whamcloud.com/13933
Reviewed-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Reviewed-by: Lai Siyao <lai.siyao@intel.com>
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>