LU-4076 fld: add local fldb to each target

LU-4076 fld: add local fldb to each target

1. Add local FLDB to each MDT, so OSD/OUT can check whether
FID is remote by looking up local FLDB, i.e. no need send RPC
to MDT0.

2. OSD will only do local lookup when checking remote FID.

3. During upgrade, MDTn(n != 0) needs to retrieve its fldb
entries from controller(MDT0) and insert into the local
FLDB.

4. MDT should also use LWP(instead of OSP) to communicate
with sequence controller (MDT0).

Signed-off-by: wang di <di.wang@intel.com>
Change-Id: I788a543aeb7305dfbad3cc41b586f9337f227119
Reviewed-on: http://review.whamcloud.com/7884
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Tested-by: Jenkins
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>