ASoC: SOF: Intel: hda-stream: store stream capabilities

Add stream_max into struct sof_intel_hda_dev to store the total hda
stream number that the platform can support, and initialize it at
stream_init.

This can be used later e.g. for stream bitmask.

Signed-off-by: Keyon Jie <yang.jie@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sof/intel/hda.h

@@ -383,6 +383,9 @@ struct sof_intel_hda_dev {
 	/* if position update IPC needed */
 	u32 no_ipc_position;
 
+	/* the maximum number of streams (playback + capture) supported */
+	u32 stream_max;
+
 	int irq;
 
 	/* DMIC device */