ACPI / dock: Actually define acpi_dock_init() as void

Commit 94add0f (ACPI / dock: Initialize ACPI dock subsystem upfront)
changed the header of acpi_dock_init() in internal.h so that it is
supposed to be a void function now, but it forgot to update its
actual definition in dock.c according to which it still is supposed
to return int.

Although that didn't cause any visible breakage or even a compiler
warning to be thrown, which is odd enough, fix it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: 3.10+ <stable@vger.kernel.org>

drivers/acpi/dock.c

@@ -1064,10 +1064,10 @@ find_dock_and_bay(acpi_handle handle, u32 lvl, void *context, void **rv)
 	return AE_OK;
 }
 
-int __init acpi_dock_init(void)
+void __init acpi_dock_init(void)
 {
 	if (acpi_disabled)
-		return 0;
+		return;
 
 	/* look for dock stations and bays */
 	acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
@@ -1075,11 +1075,10 @@ int __init acpi_dock_init(void)
 
 	if (!dock_station_count) {
 		pr_info(PREFIX "No dock devices found.\n");
-		return 0;
+		return;
 	}
 
 	register_acpi_bus_notifier(&dock_acpi_notifier);
 	pr_info(PREFIX "%s: %d docks/bays found\n",
 		ACPI_DOCK_DRIVER_DESCRIPTION, dock_station_count);
-	return 0;
 }