msm: kgsl: Add back part of VBIF soft reset registers

These were removed from the A6XX patch adding GMU support.
Add them back in so soft reset could possibly work in the
generic Adreno soft reset path.

Change-Id: Ib55c685bca4d69fe70184e3eda0add07169c6fa0
Signed-off-by: Carter Cooper <ccooper@codeaurora.org>