Make link state change monitoring use an async proc

Change-Id: Ief98bc08307652f541b7c9b87fca0499f9138b4f
Signed-off-by: Antoni S. Puimedon <asegurap@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/20259
Reviewed-by: Dan Kenigsberg <danken@redhat.com>