ACPICA/ACPI: Add new host interfaces for _OSI support

Adds install/remove interfaces so that the host can dynamically
alter the global _OSI table. Also adds support for _OSI handlers.
Additional support: new debugger command (osi), and test support in
the acpiexec utility. Adds new file, utilities/utosi.c.
ACPICA bugzilla 836.

The Linux OSL _OSI code is also changed.
acpi_osi_setup can't call acpi_install/remove_interface because ACPICA
is not initialized yet at this early time.
So we just save the osi string in acpi_osi_setup and will handle it
later in a new function acpi_osi_setup_late.

http://www.acpica.org/bugzilla/show_bug.cgi?id=836



Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>