TTY: switch tty_insert_flip_string

Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.

tty_insert_flip_string this time.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/serial/metro-usb.c b/drivers/usb/serial/metro-usb.c
index 3d25844..6264f39 100644
--- a/drivers/usb/serial/metro-usb.c
+++ b/drivers/usb/serial/metro-usb.c
@@ -127,7 +127,7 @@
 	tty = tty_port_tty_get(&port->port);
 	if (tty && urb->actual_length) {
 		/* Loop through the data copying each byte to the tty layer. */
-		tty_insert_flip_string(tty, data, urb->actual_length);
+		tty_insert_flip_string(&port->port, data, urb->actual_length);
 
 		/* Force the data to the tty layer. */
 		tty_flip_buffer_push(tty);