msm: kgsl: Fix gpu fault issue while enabling stall on page fault

Stall on page fault feature is supported on A5XX and later GPUs.
Enabling this feature on unsupported GPUs causes GPU faults.
So don't insert GPU stall related commands in ringbuffer if
not supported. But allow user to capture the GPU snapshot on
GPU page fault.

Change-Id: Ied26a5b4f44c1877b289a0ff5c0a6d47901e453d
Signed-off-by: Hareesh Gundu <hareeshg@codeaurora.org>