drm/msm: add hang_debug module param

msm.hang_debug=y will dump out current register values if the gpu locks
up, for easier debugging.

Signed-off-by: Rob Clark <robdclark@gmail.com>

diff --cc drivers/gpu/drm/msm/adreno/a3xx_gpu.c
Simple merge

diff --cc drivers/gpu/drm/msm/adreno/adreno_gpu.c
Simple merge

diff --cc drivers/gpu/drm/msm/adreno/adreno_gpu.h
Simple merge