CHROMIUM: drm/exynos: enable render node on exynos. BUG=chromium:539965 TEST=update_kernel, verify that /dev/dri/renderD128 is present Signed-off-by: Haixia Shi <hshi@chromium.org> Change-Id: I8ceabfc8d0be94388b76f1b0e288e95bc836e61b Reviewed-on: https://chromium-review.googlesource.com/304322 Commit-Ready: Haixia Shi <hshi@chromium.org> Tested-by: Haixia Shi <hshi@chromium.org> Reviewed-by: Ilja Friedel <ihf@chromium.org> Reviewed-by: Dominik Behr <dbehr@chromium.org>