LU-4659 mdd: rename forgets updating target linkea

MDD rename forgets updating target LinkEA if target is not unlinked,
which will cause LinkEA inconsistency.

Signed-off-by: Lai Siyao <lai.siyao@intel.com>
Change-Id: I9d42960da2d07d551ce08baed925bc25218fc0a4
Reviewed-on: http://review.whamcloud.com/9745
Tested-by: Jenkins
Reviewed-by: Fan Yong <fan.yong@intel.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>