LU-5249 osd: check if FLD is fully intialized

Check if FLD is fully initialized in OSD, before lookup
sequence in the local FLDB.

Change-Id: I07cbf293e617935588ce638f710868a05bdd0943
Signed-off-by: Wang Di <di.wang@intel.com>
Reviewed-on: http://review.whamcloud.com/10806
Tested-by: Jenkins
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Mike Pershin <mike.pershin@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>