c6de49574c
and external interrupt handlers should be completely unrelated. For now, just remove the obvious culprit in the nibble/ps2 case to make NTP pps signal capturing work again. External handlers should be passed to the lower level, and they should have full power and responsibility if they are installed, and their lavel should be selected by the frontend. Being here, comment out <machine/intr.h> - it is not used yet, and do some more conmetic cleanup.