ACPICA: Add EXPORT_ACPI_INTERFACES macro to external interface modules.

For Linux, there are no functional changes/binary generation differences
introduced by this patch.

This change adds a new macro to all files that contain external ACPICA
interfaces. It can be detected and used by the host (via the host-specific
header) for any special processing required for such modules. Lv Zheng.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>