ACPI / NUMA: Enable ACPI based NUMA on ARM64

Add function needed for cpu to node mapping, and enable ACPI based
NUMA for ARM64 in Kconfig

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Robert Richter <rrichter@cavium.com>
[david.daney@cavium.com added ACPI_NUMA default to y for ARM64]
Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>