drm/msm: add disp snapshot points across dpu driver

Add snapshot points across dpu driver to trigger dumps when critical
errors are hit.

changes in v5:
 - change the callers to use the snapshot function directly

Signed-off-by: Abhinav Kumar <abhinavk@codeaurora.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/1618606645-19695-8-git-send-email-abhinavk@codeaurora.org


Signed-off-by: Rob Clark <robdclark@chromium.org>