Make pci_make_tag() work with ht(4) controllers, fix a regression introduced when the macppc pci code started parsing its device tree to enumerate devices.
Make pci_make_tag() work with ht(4) controllers, fix a regression
introduced when the macppc pci code started parsing its device tree
to enumerate devices.

"ht" nodes do not have a "bus-range" property so we need to start
iterating on their PCI bridge nodes to find our devices.

orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars