LU-11997 ptlrpc: Properly swab ll_fiemap_info_key

LU-11997 ptlrpc: Properly swab ll_fiemap_info_key

It was using lustre_swab_fiemap which is incorrect since the
structures don't match.

Added lustre_swab_fiemap_info_key that swabs embedded
obdo and ll_fiemap_info_key structures.

Lustre-change: https://review.whamcloud.com/36308
Lustre-commit: 2b905746ee3b5d9dbafcdb1af5930aea18120a7b

Change-Id: Ie701163bd4c2072a0461b2d9485bc184c6548f8f
Signed-off-by: Oleg Drokin <green@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Li Xi <lixi@ddn.com>
Signed-off-by: Minh Diep <mdiep@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/36481
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>