viafb: rename display_timing to via_display_timing

The struct display_timing is specific to the via subsystem. The naming leads to
collisions with the new struct display_timing, which is supposed to be a shared
struct between different subsystems.
To clean this up, prepend the existing struct with the subsystem it is specific
to.

Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
diff --git a/drivers/video/via/share.h b/drivers/video/via/share.h
index 3158dfc..65c65c6 100644
--- a/drivers/video/via/share.h
+++ b/drivers/video/via/share.h
@@ -319,7 +319,7 @@
 	int refresh_rate;
 	int h_sync_polarity;
 	int v_sync_polarity;
-	struct display_timing crtc;
+	struct via_display_timing crtc;
 };
 
 struct io_reg {