ACPICA: Fix a regression in the acpi_evaluate_object_type() interface

ACPICA commit 9ab548ef154b992208524d61770caca90a9762be

The optional Pathname parameter inadvertently became required.
Introduced in April 2017.

Link: https://github.com/acpica/acpica/commit/9ab548ef


Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Erik Schmauss <erik.schmauss@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>