pci_host_generic: Use pci_domain_[de]activate_bus for PCI_RES_BUS resources

[imp]

I'll note in passing here that RES_BUS needing this many changes makes it not the greatest fit with resource management and if we ever do another one that requires this many special cases, we might want to think how it can be generalized. For now, though, the special cases I think are fine.

[jhb]

In D43429#992893, @imp wrote:

I'll note in passing here that RES_BUS needing this many changes makes it not the greatest fit with resource management and if we ever do another one that requires this many special cases, we might want to think how it can be generalized. For now, though, the special cases I think are fine.

I could perhaps define a pci_domain_rman that the various bus_get_rman methods could use. That would let more of the special cases fall out since bus_generic_rman_* could handle these.