videomode: videomode_from_timing work

We currently have videomode_from_timing(), which takes one
display_timing entry from display_timings.

To make it easier to use display_timing without display_timings, this
patch renames videomode_from_timing() to videomode_from_timings(), and
adds a new videomode_from_timing() which just converts a given
display_timing to videomode.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Steffen Trumtrar <s.trumtrar@pengutronix.de>
diff --git a/drivers/gpu/drm/tilcdc/tilcdc_panel.c b/drivers/gpu/drm/tilcdc/tilcdc_panel.c
index 580b74e..90ee497 100644
--- a/drivers/gpu/drm/tilcdc/tilcdc_panel.c
+++ b/drivers/gpu/drm/tilcdc/tilcdc_panel.c
@@ -173,7 +173,7 @@
 		struct drm_display_mode *mode = drm_mode_create(dev);
 		struct videomode vm;
 
-		if (videomode_from_timing(timings, &vm, i))
+		if (videomode_from_timings(timings, &vm, i))
 			break;
 
 		drm_display_mode_from_videomode(&vm, mode);