PCI code from FreeBSD

[Matthew Dillon]

   Whoop, we got some issues here.

   Before last round of commits:

       fetch http://apollo.backplane.com/DFlyMisc/dmesg_test28.boot

   After last round of commits (my test box is now broken).

       fetch http://apollo.backplane.com/DFlyMisc/dmesg_test28_bad.boot

   This is +SMP, -APIC_IO (no APIC_IO).  It worked before but now with
   the last round of commits it put all the devices on irq 2 and is
   badly broken.

						-Matt