drm: bridge: dw-hdmi: Enable CSC even for DVI

If the input pixel format is not RGB, the CSC must be enabled in order to
provide valid pixel to DVI sinks.
This patch removes the hdmi only dependency on the CSC enabling.

Reviewed-by: Jose Abreu <joabreu@synopsys.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Tested-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20170303172007.26541-4-laurent.pinchart+renesas@ideasonboard.com

drivers/gpu/drm/bridge/dw-hdmi.c

@@ -1291,8 +1291,8 @@ static void dw_hdmi_enable_video_path(struct dw_hdmi *hdmi)
 		hdmi_writeb(hdmi, clkdis, HDMI_MC_CLKDIS);
 	}
 
-	/* Enable color space conversion if needed (for HDMI sinks only). */
-	if (hdmi->sink_is_hdmi && is_color_space_conversion(hdmi))
+	/* Enable color space conversion if needed */
+	if (is_color_space_conversion(hdmi))
 		hdmi_writeb(hdmi, HDMI_MC_FLOWCTRL_FEED_THROUGH_OFF_CSC_IN_PATH,
 			    HDMI_MC_FLOWCTRL);
 	else