LU-1445 fld: allow fld lookup during recovery

LU-1445 fld: allow fld lookup during recovery

Allow fld lookup during recovery process, so OST can send fld
lookup req to MDT0 during recovery phase, instead of waiting
the recovery is done.

Signed-off-by: wang di <di.wang@intel.com>
Change-Id: I69990eb4225d98f20ce2dc197cd3c16b5c6f9617
Reviewed-on: http://review.whamcloud.com/4919
Reviewed-by: Mike Pershin <mike.pershin@intel.com>
Tested-by: Hudson
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>