During the testing of Gnome on Qualcomm Robotics platform screen
corruption has been observed. Lowering GPU's highest_bank_bit from 14 to
13 seems to fix the screen corruption.

Note, the MDSS and DPU drivers use HBB=1 (which maps to the
highest_bank_bit = 14). So this change merely works around the UBWC
swizzling issue on this platform until the real cause is found.

Fixes: e7fc9398 ("drm/msm/a6xx: Add A610 support")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/573838/Signed-off-by: Rob Clark <robdclark@chromium.org>