sparc/PCI: get rid of device resource fixups

Tell the PCI core about host bridge address translation so it can take
care of bus-to-resource conversion for us.

N.B. Leon apparently never uses initial BAR values, so it didn't matter
that we never fixed up the I/O resources from bus address to CPU addresses.

Other sparc uses pci_of_scan_bus(), which sets device resources directly
to CPU addresses, not bus addresses, so it didn't need pcibios_fixup_bus()
either.  But by telling the core about the offsets, we can nuke
pcibios_resource_to_bus().

CC: "David S. Miller" <davem@davemloft.net>
CC: sparclinux@vger.kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>