ACPI: sysfs: Use ACPI_FREE() for freeing an ACPI object

Since str_obj is allocated by ACPICA in acpi_evaluate_object_typed(),
it should be free with ACPI_FREE() rather than with kfree(), so use
the former instead of the latter for freeing it.

Signed-off-by: Kaushlendra Kumar <kaushlendra.kumar@intel.com>
Link: https://patch.msgid.link/20250822061946.472594-1-kaushlendra.kumar@intel.com


[ rjw: Subject and changelog rewrite ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>