drm/msm: add rd logging debugfs

To ease debugging, add debugfs file which can be cat/tail'd to log
submits, along with fence #.  If GPU hangs, you can look at 'gpu'
debugfs file to find last completed fence and current register state,
and compare with logged rd file to narrow down the DRAW_INDX which
triggered the GPU hang.

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

diff --cc drivers/gpu/drm/msm/Makefile
Simple merge

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

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

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

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

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

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