Merge tag 'du-fixes-20200621' of git://linuxtv.org/pinchartl/media into drm-fixes

Build fix for the R-Car DU DRM driver
Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200621021720.GA1569@pendragon.ideasonboard.com

drivers/gpu/drm/rcar-du/Kconfig

@@ -31,6 +31,7 @@ config DRM_RCAR_DW_HDMI
 config DRM_RCAR_LVDS
 	tristate "R-Car DU LVDS Encoder Support"
 	depends on DRM && DRM_BRIDGE && OF
+	select DRM_KMS_HELPER
 	select DRM_PANEL
 	select OF_FLATTREE
 	select OF_OVERLAY