tty: xtensa/iss, don't reassign to tty->port

We already do tty_port_link_device in rs_init, so we don't need to
reassign a port to tty->port. It would be too late in tty::ops::open
anyway.

Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: linux-xtensa@linux-xtensa.org
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210302062214.29627-30-jslaby@suse.czSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/xtensa/platforms/iss/console.c

@@ -48,7 +48,6 @@ static void rs_poll(struct timer_list *);
 
 static int rs_open(struct tty_struct *tty, struct file * filp)
 {
-	tty->port = &serial_port;
 	spin_lock_bh(&timer_lock);
 	if (tty->count == 1) {
 		timer_setup(&serial_timer, rs_poll, 0);