Incorporating further small changes to tidy the code, please commit if ok.

ALSA support for the SEGA Dreamcast Yamaha AICA sound device (pcm)

This patch adds ALSA sound support for pcm playback on two channels on the SEGA Dreamcast built-in sound device (the Yamaha AICA)

Add driver for the AICA sound device built into the SEGA Dreamcast

Hook it all up with the build system.

Signed-off-by: Adrian McMenamin adrian@mcmen.demon.co.uk