ASoC: SOF: pm: add definitions for S4 and S5 states

ASoC: SOF: pm: add definitions for S4 and S5 states

We currently don't have a means to differentiate between S3, S4 and
S5. Add definitions so that we have select different code paths
depending on the target state in follow-up patches.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://lore.kernel.org/r/20220616201818.130802-3-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>