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/mrst_max3110.c b/drivers/tty/serial/mrst_max3110.c
index 776431f..3b8df7b 100644
--- a/drivers/tty/serial/mrst_max3110.c
+++ b/drivers/tty/serial/mrst_max3110.c
@@ -374,7 +374,7 @@
 	for (r = 0; w; r += usable, w -= usable) {
 		usable = tty_buffer_request_room(tport, w);
 		if (usable) {
-			tty_insert_flip_string(tty, buf + r, usable);
+			tty_insert_flip_string(tport, buf + r, usable);
 			port->icount.rx += usable;
 		}
 	}