Revert "Revert "ACPI: dock driver""

This reverts 953969ddf5b049361ed1e8471cc43dc4134d2a6f commit.
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index a2b3e39..f338e40 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -334,7 +334,7 @@
 		 acpi_handle handle, int type);
 int acpi_bus_trim(struct acpi_device *start, int rmdevice);
 int acpi_bus_start(struct acpi_device *device);
-
+acpi_status acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd);
 int acpi_match_ids(struct acpi_device *device, char *ids);
 int acpi_create_dir(struct acpi_device *);
 void acpi_remove_dir(struct acpi_device *);