msm: kgsl: Remove all VBIF SMMU CB2 registers from snapshot

Reading these registers which are part of the secured context bank
and locked down by TZ in snapshot is problematic and causes XPU
violations. These registers are never used for 8084 so its ok
for us to remove these.

Change-Id: I87d098fde46e6a9f0e5d0e35951e6582f99a2322
Signed-off-by: Shrenuj Bansal <shrenujb@codeaurora.org>