Revert "sound_control: remove useless define."

This reverts commit 99a5241c10d00966b9ad7b6325566703a6191c22.
Revert "sound_control: add headset, speaker and mic gain interfaces. Also add the sysfs control file."

This reverts commit 0195a66aed68df51a91f363c0aa9f902bc1e4c71.