LU-14854 mdd: proper handle error in mdd_swap_layouts()

LU-14854 mdd: proper handle error in mdd_swap_layouts()

Only restore object's HSM xattr on error if it's for
SWAP_LAYOUTS_MDS_HSM.

Lustre-change: https://review.whamcloud.com/44319
Lustre-commit: 7648c1c905b0976fc789cfd9c6bac382389385ee

Signed-off-by: Bobi Jam <bobijam@whamcloud.com>
Change-Id: I9d4c58cd3107c3900e72a0946d0ec7d7286dd43f
Reviewed-by: Lai Siyao <lai.siyao@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/46021
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Bobi Jam <bobijam@hotmail.com>