get_mirror
r = get_mirror(ms, ti, m, argv);
.get_mirror = tpo_td043_get_hmirror,
if (!dssdev->driver->get_mirror)
mirror = dssdev->driver->get_mirror(dssdev);
if (!dssdev->driver->set_mirror || !dssdev->driver->get_mirror)
bool (*get_mirror)(struct omap_dss_device *dssdev);