staging/lustre/ldlm: revert changes to ldlm_cancel_aged_policy()

The changes to ldlm_cancel_aged_policy() introduced from LU-4300
was incorrect. This patch revert this part of changes.

Signed-off-by: Niu Yawei <yawei.niu@intel.com>
Reviewed-on: http://review.whamcloud.com/12448
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-5727


Reviewed-by: Bobi Jam <bobijam@gmail.com>
Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>