drm/msm/a6xx: fix incorrectly set uavflagprd_inv field for A650

Value was shifted in the wrong direction, resulting in the field always
being zero, which is incorrect for A650.

Fixes: d0bac4e9

 ("drm/msm/a6xx: set ubwc config for A640 and A650")
Signed-off-by: Jonathan Marek <jonathan@marek.ca>
Reviewed-by: Akhil P Oommen <akhilpo@codeaurora.org>
Link: https://lore.kernel.org/r/20210513171431.18632-4-jonathan@marek.ca
Signed-off-by: Rob Clark <robdclark@chromium.org>