usb: Fix typo in `struct usb_host_interface' comment

The descriptor member `bNumEndpoints' is plural.
Signed-off-by: Chris Rorvick <chris@rorvick.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

include/linux/usb.h

@@ -82,7 +82,7 @@ struct usb_host_interface {
 	int extralen;
 	unsigned char *extra;   /* Extra descriptors */
 
-	/* array of desc.bNumEndpoint endpoints associated with this
+	/* array of desc.bNumEndpoints endpoints associated with this
 	 * interface setting.  these will be in no particular order.
 	 */
 	struct usb_host_endpoint *endpoint;