PCI: rcar: Simplify host bridge window iteration

The switch is the only statement in the resource_list_for_each_entry()
loop, so remove unnecessary cases and "continue" statements in the switch.
Inline rcar_pcie_release_of_pci_ranges(), which is only called once.

No functional change intended.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>