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/net/irda/ircomm/ircomm_tty.c b/net/irda/ircomm/ircomm_tty.c
index 14b08e3..2491f6f 100644
--- a/net/irda/ircomm/ircomm_tty.c
+++ b/net/irda/ircomm/ircomm_tty.c
@@ -452,7 +452,7 @@
 		   self->line, self->port.count);
 
 	/* Not really used by us, but lets do it anyway */
-	tty->low_latency = (self->port.flags & ASYNC_LOW_LATENCY) ? 1 : 0;
+	self->port.low_latency = (self->port.flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 
 	/*
 	 * If the port is the middle of closing, bail out now