audio: Add support for FLAC in compress offload path

- Add new audio format for FLAC
- Add FLAC in valid formats list
- Add bitWidth in offload info

Change-Id: Ic716aff8b7cdb28b03f32f686eca33ff0beb981c
Merge remote-tracking branch 'CM/cm-11.0' into HEAD
Merge remote-tracking branch 'upstream/kitkat' into kitkat