ACPI: NUMA: Consolidate header includes

The header file acpi/acpi_numa.h is included whether CONFIG_ACPI is
defined or not.

Include it only once before the #ifdef/#else/#endif preprocessor
directives and fix the following make includecheck warning:

	acpi/acpi_numa.h is included more than once

Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>