drm/msm/gpu: Add submit queue queries

Add the capability to query information from a submit queue.
The first available parameter is for querying the number of GPU faults
(hangs) that can be attributed to the queue.

This is useful for implementing context robustness. A user context can
regularly query the number of faults to see if it is responsible for any
and if so it can invalidate itself.

This is also helpful for testing by confirming to the user  driver if a
particular command stream caused a fault (or not as the case may be).

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>