LU-3677 mdt: Set HSM dirty open-for-write file when evicted.

LU-3677 mdt: Set HSM dirty open-for-write file when evicted.

Fix regression introduced by LU-1303 (5165cdd). Previously,
MDS_CLOSE_CLEANUP was used to detect file closing, due to eviction.
This flag is no more since 5165cdd.

It completely removed this symbol.

Signed-off-by: Aurelien Degremont <aurelien.degremont@cea.fr>
Change-Id: I20e18103fe085672f499c956e831564e45bd5200
Reviewed-on: http://review.whamcloud.com/7195
Tested-by: Hudson
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Fan Yong <fan.yong@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>