Add support for remote control microphones.

GFRM210: ti-rcu-audio
TI supplies a RAS_lib to convert their proprietary
audio codec to PCM. Provide a daemon which Blue/Z
can send messages to, via a Unix domain socket in
abstract namespace "\0rc_audio_ti"

GFRM100: gfrm100-rcu-audio
Handle GFRM100 using HID RAW, watching for AUDIO_DATA
events as they fly by. The Broadcom BT chip in GFRM100
packages audio data as giant HID events, and handling
non-standard stuff like that is why HID RAW exists.
GFRM100 sends 16KHz PCM, no postprocessing is required.

ti-rcu-audio and gfrm100-rcu-audio package audio samples into
a protobuf defined in remote_control_audio.proto, and send it
to a Unix domain socket in abstract namespace "\0rcu_audio".

gfrm-voice-demo
In the real system, audio data will be handled by the TV
software as a continuous stream and uploaded to the speech
API as it arrives. For early testing, provide a gfrm-voice-demo
which records PCM data into WAV files.

Also:
Rename BUILD_IBEACON to BUILD_BLUETOOTH as we now
have a number of utilities to be built on Bluetooth
capable platforms: ibeacon, eddystone, ti-rcu-audio,
gfrm100-rcu-audio, gfrm-voice-demo.

Change-Id: I52da6a424dd4b69c3295544db2bbfd97f7bbc3ca
12 files changed