USB: add missing kerneldoc line for "needs_binding"

This patch (as1117) adds a kerneldoc line for the "needs_binding"
field in struct usb_interface.  It was accidentally omitted when the
field was added.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

include/linux/usb.h

@@ -110,6 +110,8 @@ enum usb_interface_condition {
  * @sysfs_files_created: sysfs attributes exist
  * @needs_remote_wakeup: flag set when the driver requires remote-wakeup
  *	capability during autosuspend.
+ * @needs_binding: flag set when the driver should be re-probed or unbound
+ *	following a reset or suspend operation it doesn't support.
  * @dev: driver model's view of this device
  * @usb_dev: if an interface is bound to the USB major, this will point
  *	to the sysfs representation for that device.