ASoC: SOF: Intel: pci-mtl: Allow DSPless mode

set the dspless_mode_supported flag to true for mtl family to allow
DSPless mode.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Link: https://lore.kernel.org/r/20230404092115.27949-11-peter.ujfalusi@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sof/intel/pci-mtl.c

@@ -31,6 +31,7 @@ static const struct sof_dev_desc mtl_desc = {
 	.chip_info = &mtl_chip_info,
 	.ipc_supported_mask	= BIT(SOF_INTEL_IPC4),
 	.ipc_default		= SOF_INTEL_IPC4,
+	.dspless_mode_supported	= true,		/* Only supported for HDaudio */
 	.default_fw_path = {
 		[SOF_INTEL_IPC4] = "intel/sof-ipc4/mtl",
 	},