vm: Update domains list for disks attached to vm after LSM

Change-Id: I6cda08eea5e94f4cb9039ce08eac2bfe0861e260
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1036680
Signed-off-by: Yeela Kaplan <ykaplan@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/22536
Reviewed-by: Federico Simoncelli <fsimonce@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/22562
Reviewed-by: Allon Mureinik <amureini@redhat.com>