Update notes for submitted changes

* libhardware_legacy: Clean up all the audio ifdefs
* AudioPolicyManagerBase : MUTE_TIME_MS reduced to 500ms
* audio: Add support for compressed VoIP
* audio: Add support for DOLBY DD+ decoding
* audio: Do not allow Compress offload mode for AV streaming content
* libhardware: Fix merge damage which was breaking direct output
* audio: fix for multi-channel HDMI playback