ASoC: SOF: Intel: hda-mlink: add helper to check cmdsync

This helper is an optimization where sync_go is only called when the
cmdsync field is actually set to a non-zero value.

Since this is also only used by SoundWire for now, only expose the
_unlocked version.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20230404104127.5629-15-peter.ujfalusi@linux.intel.com


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