ACPI / PCI: Stub out pci_acpi_crs_quirks() and make it x86 specific

For pci_acpi_crs_quirks(), ia64 already doesn't use it, and we can
not foresee it should be used in ARM64, so stub out pci_acpi_crs_quirks()
to avoid introducing platform specific dummy stub function.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Reviewed-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>