ASoC: es8323: power and mixer controls cleanup and

Merge series from Shimrra Shai <shimrrashai@gmail.com>:

This is a revision of a previous patch submission of mine wherein one
part was accepted and one part was not. It was originally phrased for
a particular device using the ES8323 CODEC, and I was advised to make
the mixer controls user-selectable so it was not tied to the needs of
any specific device. This submission brings the DAC and mixer controls
for basic audio playback on this CODEC into line with the DAPM
infrastructure and enables their operation through the standard mixer
interface.