drm/radeon: Select BACKLIGHT_LCD_SUPPORT

Explicitly select BACKLIGHT_LCD_SUPPORT to satisfy the direct dependency
of BACKLIGHT_CLASS_DEVICE.

Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/Kconfig

@@ -128,6 +128,7 @@ config DRM_RADEON
 	select POWER_SUPPLY
 	select HWMON
 	select BACKLIGHT_CLASS_DEVICE
+	select BACKLIGHT_LCD_SUPPORT
 	select INTERVAL_TREE
 	help
 	  Choose this option if you have an ATI Radeon graphics card.  There