change channel interface - kobj implementation coming soonish
make pcm_makelinks not panic if modular
add pcm_unregister()
these changes support newpcm kld unloading, but this is only implemented
by ds1.c
modify driver capability reporting format to list every audio format
seperately- required for above and because we could not previously indicate
that mono was unsupported.
there should be no functional impact.
rewrite ess mixer to use native registers
rewrite play/rec code to use more accurate timer when available
add code to use audio2 for playback, but disable it as no irqs are generated