LU-8998 pfl: layout LFSCK handles PFL file

LU-8998 pfl: layout LFSCK handles PFL file

Enhance the layout LFSCK logic to handle the PFL file,
including all the inconsistent cases corresponding to
the non-PFL file cases. In addition, for PFL file, the
LFSCK can also verify and recover the PFL extent range.

Reviewed-on: https://review.whamcloud.com/24883

Signed-off-by: Fan Yong <fan.yong@intel.com>
Change-Id: Iec5ac57fd556330130e33f187c6fbf8cc24e67b8
Reviewed-by: Niu Yawei <yawei.niu@intel.com>
Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>