'flags 1' on the sb? kernel configuration file line (because it frobs a
noncontiguous IO port to configure the Jazz16 extensions).
Also, remove static sb_device structure and fill in user's buffer on
each request.
* Snap the sample rate when setting it, and remember only the time constant.
* Set the time constant when changing between play/record.
* Always return the actual sample rate with AUDIO_GETINFO.
* Add more delays while writing registers.
* Replace sc_dma{in,out}_inprogress with sc_dmadir.
* Eliminate the need for sc_locked.
* Add more DPRINTF()s.
