Clear pending interrupts before starting a DMA transfer. If an interrupt
occurs while the HDC9224 is doing DMA, the transfered data will be
scrambled (without giving any errors, quite bad).
since NetBSD 1.2 (!) It also uses interrupts instead of polling now.
Also fix the DMA area locking between SCSI and MFM disks.
Still missing - floppy support.
a char *, because that's what was really intended, and because
if the print function modifies the string, various things could become
unhappy (so the string should _not_ be modified).
mrg