drm/omap: remove unused get_dimensions()

get_dimensions function pointer is not used, remove it.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

drivers/gpu/drm/omapdrm/dss/omapdss.h

@@ -690,8 +690,6 @@ struct omap_dss_driver {
 
 	void (*get_resolution)(struct omap_dss_device *dssdev,
 			u16 *xres, u16 *yres);
-	void (*get_dimensions)(struct omap_dss_device *dssdev,
-			u32 *width, u32 *height);
 
 	int (*check_timings)(struct omap_dss_device *dssdev,
 			     struct videomode *vm);