msm: kgsl: Take GMU snapshot on GMU failures

GMU can fail to turn on GX or it can fail the
START HFI. So take snapshot and put GMU in NMI.
When this happens, kgsl will call gmu_stop()
and as GMU is already in fault aka NMI, reset
the GMU and GPU.

Change-Id: Iafc9b34063a7ff2415d3462dd289b52e425fbf3b
Signed-off-by: Harshdeep Dhatt <hdhatt@codeaurora.org>