Executing `asctl set r 96000` no longer results in weird sample rates
being set on the audio devices. SB16 checks for a sample rate between 1
and 44100 Hz, while AC97 implements double-rate support which allows
sample rates between 8kHz and 96kHZ.
The new asctl (audio server control) utility expands on avol with a
completely new command line interface (documented in the man page) that
supports retrieving and setting all exposed audio server settings, like
volume and sample rate. This is currently the only user-facing way of
changing the sample rate.
