msm: kgsl: Dump snapshot for long IB timeout

Dump snapshot when long IB timeout is detected. The GPU
command processor is halted on long IB timeout detection,
this will halt the GPU pipeline, dumping the snapshot at
this point is safe and gives us information to debug
long IB timeout.

Change-Id: I51bb73b66e11c3b6945c3dfe92af03e21e3c0e62
Signed-off-by: Tarun Karra <tkarra@codeaurora.org>