driver core: clean up device_shutdown

device_shutdown does not need to be in a separate file.  Move it into
the driver core file where it belongs.

This also moves us one more step closer to making devices_kset static,
now only the crazy sysdevs are keeping that from happening...

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/base/core.c b/drivers/base/core.c
index d2de2d5..b3a931f 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -1415,5 +1415,23 @@
 	put_device(dev);
 	return error;
 }
-
 EXPORT_SYMBOL_GPL(device_move);
+
+/**
+ * device_shutdown - call ->shutdown() on each device to shutdown.
+ */
+void device_shutdown(void)
+{
+	struct device * dev, *devn;
+
+	list_for_each_entry_safe_reverse(dev, devn, &devices_kset->list,
+				kobj.entry) {
+		if (dev->bus && dev->bus->shutdown) {
+			dev_dbg(dev, "shutdown\n");
+			dev->bus->shutdown(dev);
+		} else if (dev->driver && dev->driver->shutdown) {
+			dev_dbg(dev, "shutdown\n");
+			dev->driver->shutdown(dev);
+		}
+	}
+}