LU-9499 lfsck: set target bitmap properly

LU-9499 lfsck: set target bitmap properly

If the notify from the peer server has LF_INCOMPLETE flags,
then record it in the target bitmap unconditionally to avoid
missing to update the bitmap for some corner cases.

This patch also addes more debug information when the LFSCK
updates the bitmap and handle double_scan_result.

Signed-off-by: Fan Yong <fan.yong@intel.com>
Change-Id: I3a6195136d608aa47e59e61f95c92978503e3a4b
Reviewed-on: https://review.whamcloud.com/27632
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Lai Siyao <lai.siyao@intel.com>
Reviewed-by: Bobi Jam <bobijam@hotmail.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>