LU-9362 lfs: getstripe print last init-ed component info

LU-9362 lfs: getstripe print last init-ed component info

If getstripe asks for part of stripe information of a PFL file,
lfs should print the last instantiated component stripe info.

Signed-off-by: Bobi Jam <bobijam.xu@intel.com>
Change-Id: Iebdc4d44e47a25ef8445fda240b25975f8dbcbbe
Reviewed-on: https://review.whamcloud.com/26947
Tested-by: Jenkins
Reviewed-by: Niu Yawei <yawei.niu@intel.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: James Nunez <james.a.nunez@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>