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/tty/serial/ifx6x60.c b/drivers/tty/serial/ifx6x60.c
index 675d94a..bfb634e 100644
--- a/drivers/tty/serial/ifx6x60.c
+++ b/drivers/tty/serial/ifx6x60.c
@@ -672,7 +672,7 @@
 	struct tty_struct *tty = tty_port_tty_get(&ifx_dev->tty_port);
 	if (!tty)
 		return;
-	tty_insert_flip_string(tty, chars, size);
+	tty_insert_flip_string(&ifx_dev->tty_port, chars, size);
 	tty_flip_buffer_push(tty);
 	tty_kref_put(tty);
 }