ia64/PCI/ACPI: Use common ACPI resource parsing interface for host bridge

Use common ACPI resource parsing interface to parse ACPI resources for
PCI host bridge, so we could share more code between IA64 and x86.
Later we will consolidate arch specific implementations into ACPI core.
Tested-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>