msm: kgsl: Disable HLSQ register reads from snapshot

Reading the A3XX HLSQ registers during a GPU hang recovery might cause
the device to hang.  Disable the the HLSQ register reads that would
cause recovery to fail until the failures are better understood.

Change-Id: I1553025fbd824bfacf91f062372d5731cd905cc4
Signed-off-by: Carter Cooper <ccooper@codeaurora.org>