__acpi_map_pxm_to_node() and acpi_get_pxm() are only used within
drivers/acpi/numa.c.  This makes them static and removes their
declarations.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>