drm/msm/a6xx: Update the GMU bus tables for sc7180

Fixup the GMU bus table values for the sc7180 target.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Fixes: e812744c

 ("drm: msm: a6xx: Add support for A618")
Signed-off-by: Rob Clark <robdclark@chromium.org>