to a softc, rather than a unit number. Add a "dq_softc" member
to struct devqueue; this is a temporary measure until the
dma/controller/device callback spaghetti is untangled.
YAY! No more need for dcafastservice!
HIL: squish instances of "(void) splhil()" and "(void) spl0();".
be done. Set up a structure filled with function pointers in the
controller-specific probe routines, and jump through them, instead of
if()'ing our way though each operation.
Be a little more discriptive; print out the controller type found
during the probe in a way that's somewhat meaningful.