drm/msm: Fix shutdown

drm/msm: Fix shutdown

When rebooting on my sc7280-herobrine based device, I got a
crash. Upon debugging, I found that I was in msm_drv_shutdown() and my
"pdev" was the one associated with mdss_probe().

From source, I found that mdss_probe() has the line:
  platform_set_drvdata(pdev, mdss);
...where "mdss" is of type "struct msm_mdss *".

Also from source, I saw that in msm_drv_shutdown() we have the line:
  struct msm_drm_private *priv = platform_get_drvdata(pdev);

This is a mismatch and is the root of the problem.

Further digging made it apparent that msm_drv_shutdown() is only
supposed to be used for parts of the msm display framework that also
call msm_drv_probe() but mdss_probe() doesn't call
msm_drv_probe(). Let's remove the shutdown functon from msm_mdss.c.

Digging a little further, code inspection found that two drivers that
use msm_drv_probe() weren't calling msm_drv_shutdown(). Let's add it
to them.

Fixes: 99686cd09e3a ("drm/msm: make mdp5/dpu devices master components")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/484975/
Link: https://lore.kernel.org/r/20220504163900.v2.1.Iaebd35e60160fc0f2a50fac3a0bf3b298c0637c8@changeid
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>