ASoC: SOF: Intel: introduce new op to handle dsp power down

DSP core power down sequences are different between cavs platforms and MTL.
Signed-off-by: Fred Oh <fred.oh@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Link: https://lore.kernel.org/r/20220922213644.666315-2-ranjani.sridharan@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sof/intel/shim.h

@@ -186,6 +186,7 @@ struct sof_intel_dsp_desc {
 	enum sof_intel_hw_ip_version hw_ip_version;
 	bool (*check_sdw_irq)(struct snd_sof_dev *sdev);
 	bool (*check_ipc_irq)(struct snd_sof_dev *sdev);
+	int (*power_down_dsp)(struct snd_sof_dev *sdev);
 	int (*cl_init)(struct snd_sof_dev *sdev, int stream_tag, bool imr_boot);
 };