drm/tilcdc: add support for LCD panels (v5)

Add an output panel driver for LCD panels.  Tested with LCD3 cape on
beaglebone.

v1: original
v2: s/of_find_node_by_name()/of_get_child_by_name()/ from Pantelis
    Antoniou
v3: add backlight support
v4: rebase to latest of video timing helpers
v5: remove some unneeded fields from panel-info struct, add DT bindings
    docs

Signed-off-by: Rob Clark <robdclark@gmail.com>
Tested-by: Koen Kooi <koen@dominion.thruhere.net>
diff --git a/drivers/gpu/drm/tilcdc/Kconfig b/drivers/gpu/drm/tilcdc/Kconfig
index ee9b592..ae14fd6 100644
--- a/drivers/gpu/drm/tilcdc/Kconfig
+++ b/drivers/gpu/drm/tilcdc/Kconfig
@@ -4,6 +4,9 @@
 	select DRM_KMS_HELPER
 	select DRM_KMS_CMA_HELPER
 	select DRM_GEM_CMA_HELPER
+	select OF_VIDEOMODE
+	select OF_DISPLAY_TIMING
+	select BACKLIGHT_CLASS_DEVICE
 	help
 	  Choose this option if you have an TI SoC with LCDC display
 	  controller, for example AM33xx in beagle-bone, DA8xx, or