msm: kgsl: Add preemption debug info to snapshot dump

Add the current, previous and next ringbuffer to snapshot dump.
Also add preemption records and preemption SMMU info to snapshot dump.
Increase the size of snapshot static memory to 600k to have enough
space for new buffers being dumped.

Change-Id: I9b2d42fa15dc9a4c9cccf61a442fcc95b87725af
Signed-off-by: Shubhraprakash Das <sadas@codeaurora.org>