$Id$ information, and other code to make sound driver compile and work
correctly with FreeBSD.
Integrate changes obtained from Sujal Patel. These changes are:
o local.h: reverse option logic from EXCLUDE_* to AUDIO_*
o pas2_mixer.c: small addition
o ad1848.c: minor change with macro names
o sequencer.c: minor change with note check
o many spelling corrections in comments in about every other file
66e456c58e