ASoC: qcom: sc7180: Add missing PM ops

Use PM ops snd_soc_pm_ops to handle suspend/resume like other machine
drivers.

Signed-off-by: Cheng-Yi Chiang <cychiang@chromium.org>
Link: https://lore.kernel.org/r/20201109103415.607495-1-cychiang@chromium.org


Signed-off-by: Mark Brown <broonie@kernel.org>