ACPICA: expose OSI version

Expose acpi_gbl_osi_data so that code outside of ACPICA can check
the value of the last successfull _OSI call.  The definitions for
OSI versions are moved to actypes.h so that other components can
access them too.

Based on a patch from Matthew Garrett which in turn was based on
an earlier patch from Seth Forshee.

[rjw: Changelog]
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>