OMAP: DSS2: move timing functions

Move check/set/get_timings() from omap_dss_device to omap_dss_driver.

This is part of a larger patch-set, which moves the control from omapdss
driver to the display driver.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@nokia.com>
diff --git a/drivers/video/omap2/displays/panel-taal.c b/drivers/video/omap2/displays/panel-taal.c
index 484a618..a722733 100644
--- a/drivers/video/omap2/displays/panel-taal.c
+++ b/drivers/video/omap2/displays/panel-taal.c
@@ -516,8 +516,6 @@
 
 	dev_set_drvdata(&dssdev->dev, td);
 
-	dssdev->get_timings = taal_get_timings;
-
 	/* if no platform set_backlight() defined, presume DSI backlight
 	 * control */
 	if (!dssdev->set_backlight)
@@ -1118,6 +1116,8 @@
 	.run_test	= taal_run_test,
 	.memory_read	= taal_memory_read,
 
+	.get_timings	= taal_get_timings,
+
 	.driver         = {
 		.name   = "taal",
 		.owner  = THIS_MODULE,