This register's magic value differs wildly between different GPUs, use
the hardcoded data instead of trying to make some logic out of it.
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/611096/Signed-off-by: Rob Clark <robdclark@chromium.org>