tty: fix missing assignment

We're trying to save the termios state and we need to allocate a buffer
to do it. Smatch complains that the buffer is leaked at the end of the
function.

Signed-off-by: Dan Carpenter <[e-mail]>
Signed-off-by: Alan Cox <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/tty/tty_io.c

···
 			pr_warn("tty: no memory to save termios state.\n");
 			return;
 		}
+		tty->driver->termios[idx] = tp;
 	}
 	*tp = tty->termios;
 }