nozomi: quick fix for the close/close bug

Nozomi goes wrong if you get the sequence

	open
	open
	close

	[stuff]
	close

which turns out to occur on some ppp type setups.

This is a quick patch up for the problem. It's not really fixing Nozomi
which completely fails to implement tty open/close semantics and all the
other needed stuff. Doing it right is a rather more invasive patch set and
not one that will backport.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/char/nozomi.c

@@ -1651,10 +1651,10 @@ static void ntty_close(struct tty_struct *tty, struct file *file)
 
 	dc->open_ttys--;
 	port->count--;
-	tty_port_tty_set(port, NULL);
 
 	if (port->count == 0) {
 		DBG1("close: %d", nport->token_dl);
+		tty_port_tty_set(port, NULL);
 		spin_lock_irqsave(&dc->spin_mutex, flags);
 		dc->last_ier &= ~(nport->token_dl);
 		writew(dc->last_ier, dc->reg_ier);