ACPICA: Fix memory leak on unusual memory leak

Fixes a single-object memory leak on a store-to-reference method
invocation. ACPICA BZ 1439.

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>

drivers/acpi/acpica/psargs.c

@@ -890,6 +890,10 @@ acpi_ps_get_next_arg(struct acpi_walk_state *walk_state,
 						      ACPI_POSSIBLE_METHOD_CALL);
 
 			if (arg->common.aml_opcode == AML_INT_METHODCALL_OP) {
+
+				/* Free method call op and corresponding namestring sub-ob */
+
+				acpi_ps_free_op(arg->common.value.arg);
 				acpi_ps_free_op(arg);
 				arg = NULL;
 				walk_state->arg_count = 1;