Merge tag 'mediatek-drm-fixes-5.10' of https://git.kernel.org/pub/scm/linux/kernel/git/chunkuang.hu/linux into drm-fixes

Mediatek DRM Fixes for Linux 5.10

1. Remove unused variable.
2. Modify horizontal front/back porch byte formula.

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Chun-Kuang Hu <chunkuang.hu@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201123234131.387-1-chunkuang.hu@kernel.org