TTY: move low_latency to tty_port

One point is to have less places where we actually need tty pointer.
The other is that low_latency is bound to buffer processing and
buffers are now in tty_port. So it makes sense to move low_latency to
tty_port too.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/char/pcmcia/synclink_cs.c b/drivers/char/pcmcia/synclink_cs.c
index 9bdfe27..92dc732 100644
--- a/drivers/char/pcmcia/synclink_cs.c
+++ b/drivers/char/pcmcia/synclink_cs.c
@@ -2522,7 +2522,7 @@
 		goto cleanup;
 	}
 
-	tty->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
+	port->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 
 	spin_lock_irqsave(&info->netlock, flags);
 	if (info->netcount) {