LU-10894 dom: per-resource ELC for WRITE lock enqueue

LU-10894 dom: per-resource ELC for WRITE lock enqueue

Improve client write lock enqueue by doing ELC for any
read lock on the same resource. This helps with read/write
access, e.g. compilebench shows ~10% better results with
about 45% less ldlm cancel RPCs.

In mdc_enqueue_send() collect resource unused read locks
and pack them into enqueue request.

The ldlm_cancel_resource_local() is changed also to don't
skip DOM lock if it is set in policy explicitly

Signed-off-by: Mikhail Pershin <mpershin@whamcloud.com>
Change-Id: I06ece95d837495e2e970ce670db61ba0aa4e1ab4
Reviewed-on: https://review.whamcloud.com/34736
Tested-by: Jenkins
Reviewed-by: Patrick Farrell <pfarrell@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Alexey Lyashkov <c17817@cray.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>