ASoC: Intel: sof_pcm512x: add support for SOF platforms with pcm512x

Add support for multiple platforms, e.g. Apollolake based, using the
pcm512x audio codec.

The SOF developers and CI rely on the Up^2 and Hifiberry DAC+ boards
based on this codec for tests.

Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Signed-off-by: Pan Xiuli <xiuli.pan@linux.intel.com>
Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200129223603.2569-2-pierre-louis.bossart@linux.intel.com


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