msm: kgsl: add GMUCX and GMUAO registers in snapshot for A702

GMUCX and GMUAO related registers are not being added in snapshot
for A702 GPU. Capture these register values so they are available
as part of snapshot to help while debugging.

Change-Id: I23091110c8a0a715b8381754589a6d8531ed717c
Signed-off-by: Pranav Patel <pranavp@codeaurora.org>