drm/msm: Split out devfreq handling

Before we start adding more cleverness, split it into it's own file.

Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20210726144653.2180096-2-robdclark@gmail.com
Signed-off-by: Rob Clark <robdclark@chromium.org>
5 files changed