registering their interrupts with rman as though they were going through
the ISA pic. This prevents a conflict between isa & pci for irqs on such
machines.
Also hookup the chipset struct before calling platform.pci_intr_init().
This allows me to call inw/outw down in the platform code.
Add interrupt printfs to match the CIA chipset.
Reviewed by: dfr
Tested by: wilko