ASoC: Intel: Remove SST ACPI component

baytrail and haswell solutions present within sound/soc/intel are the
only users of sst-acpi componenent and with them removed it becomes
redundant so remove it too.

Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Liam Girdwood <liam.r.girdwood@intel.com>
Link: https://lore.kernel.org/r/20201006064907.16277-6-cezary.rojewski@intel.com


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