um: Use tty_port_operations->destruct

As we setup the SIGWINCH handler in tty_port_operations->activate
it makes sense to tear down it in ->destruct.

Signed-off-by: Richard Weinberger <richard@nod.at>

arch/um/drivers/stdio_console.c

@@ -110,7 +110,6 @@ static const struct tty_operations console_ops = {
 	.set_termios 		= line_set_termios,
 	.throttle 		= line_throttle,
 	.unthrottle 		= line_unthrottle,
-	.cleanup		= line_cleanup,
 	.hangup			= line_hangup,
 };