Pack parent FID in getattr request if OBD_CONNECT2_GETATTR_PFID is
enabled, otherwise fill it with target FID for backward compatibility.

Fixes: f9a2da63

 ("LU-13437 mdt: don't fetch LOOKUP lock for remot...")
Test-Parameters: clientversion=2.12 testlist=sanity env=SANITY_EXCEPT="27M 151 156"
Test-Parameters: serverversion=2.12 testlist=sanity env=SANITY_EXCEPT="56 165 205b"
Signed-off-by: Lai Siyao <lai.siyao@whamcloud.com>
Change-Id: Idcf8388b65dee1f0a09a53b240ce8303f3c6ff75
Reviewed-on: https://review.whamcloud.com/39290


Tested-by: jenkins <devops@whamcloud.com>
Reviewed-by: Neil Brown <neilb@suse.de>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>