ACPICA: Dispatcher: Fix an unbalanced lock exit path in acpi_ds_auto_serialize_method()

There is a lock unbalanced exit path in acpi_ds_initialize_method(),
this patch corrects it.

Fixes: 441ad11d078f (ACPICA: Dispatcher: Fix a mutex issue for method auto serialization)
Tested-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/acpica/dsmethod.c

@@ -128,7 +128,7 @@ acpi_ds_auto_serialize_method(struct acpi_namespace_node *node,
 	if (ACPI_FAILURE(status)) {
 		acpi_ds_delete_walk_state(walk_state);
 		acpi_ps_free_op(op);
-		return_ACPI_STATUS(status);
+		goto unlock;
 	}
 
 	walk_state->descending_callback = acpi_ds_detect_named_opcodes;