drm/meson: Add support for HDMI encoder and DW-HDMI bridge + PHY

The Amlogic Meson GXBB/GXL/GXM SoCs embeds a Synopsys DesignWare HDMI TX
Controller with a custom Bridge + PHY around the Controller.

This driver makes uses of all the custom PHY plat data callbacks and enables
the compatible HDMI modes to be configured as a drm_encoder instance.

Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
diff --git a/drivers/gpu/drm/meson/meson_drv.h b/drivers/gpu/drm/meson/meson_drv.h
index 6195327..5e8b392 100644
--- a/drivers/gpu/drm/meson/meson_drv.h
+++ b/drivers/gpu/drm/meson/meson_drv.h
@@ -47,6 +47,9 @@ struct meson_drm {
 
 	struct {
 		unsigned int current_mode;
+		bool hdmi_repeat;
+		bool venc_repeat;
+		bool hdmi_use_enci;
 	} venc;
 };