AC97 Codec
o Enhanced current WM97xx support to provide additional controls and
use the kcontrol suffix naming convention.
o Added AC97_HAS_NO_MIC, AC97_HAS_NO_TONE and AC97_HAS_NO_STD_PCM.
o Cleaned up WM97xx related comments.
o Removed some wm9713 double mono controls and replaced with stereo
controls.