Changes:
Added a pci-EISA bridge device and associated glue to the prep port.
Adapted from i386.
Change pci_intr_fixup_*() to pass the pin argument on all platforms.
Make PCI_NETBSD_CONFIGURE leave the MPIC alone. We map it separately.
7024 kernel was also succ. tested on an IBM 7043, so no regression there.
