drm/msm/a7xx: Add missing register writes from downstream

This isn't known to fix anything yet, but it's a good idea to add it.

Signed-off-by: Connor Abbott <cwabbott0@gmail.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/592043/


Signed-off-by: Rob Clark <robdclark@chromium.org>