drm/msm/gpu: Cancel idle/boost work on suspend

With system suspend using pm_runtime_force_suspend() we can't rely on
the pm_runtime_get_if_in_use() trick to deal with devfreq callbacks
after (or racing with) suspend.  So flush any pending idle or boost
work in the suspend path.

Signed-off-by: Rob Clark <robdclark@chromium.org>
Link: https://lore.kernel.org/r/20220108180913.814448-3-robdclark@gmail.com


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