device-amazon-biscuit: add alsa and pulseaudio configs

- Add UCM2 configurations for biscuit
- Add udev rule to switch headphone output
- Add asound config
- Add pulseaudio configs

This commit provides a basic pulseaudio setup for biscuit. The device appears
to only support 48kHz audio. Resampled 44kHz audio crackles and pops currently
due to the buffer underrunning. Some more tweaking may be needed to improve
audio playback quality.