switch device_get_devnode() and ->devnode() to umode_t *

both callers of device_get_devnode() are only interested in lower 16bits
and nobody tries to return anything wider than 16bit anyway.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

include/linux/usb.h

@@ -935,7 +935,7 @@ extern struct bus_type usb_bus_type;
  */
 struct usb_class_driver {
 	char *name;
-	char *(*devnode)(struct device *dev, mode_t *mode);
+	char *(*devnode)(struct device *dev, umode_t *mode);
 	const struct file_operations *fops;
 	int minor_base;
 };