fireball: audio: separate speaker profiles for voice/media

The in-call speakerphone volume is drastically lower than the speaker
volume for media and notifications.  Use a separate "Voice Speaker"
profile and up the volumes.

Change-Id: I17061c7234fef5c577bec1bbc0016595ff0847cd
fireball: audio: headphone/headset/handset volume adjustments

1) significantly lower volumes in speaker+headset combo profile
2) increase headphones volume
3) increase handset tx volume

Change-Id: I8b3d7db307efba751c278dc51898b1d4bfd085ee
fireball: move hardware button config to device overlay

Requires: http://review.cyanogenmod.org/51680

Change-Id: Id5aa04bc62f9d5b9e593a9ec043f828133326a9b