TTY: call tty_port_destroy in the rest of drivers

After commit "TTY: move tty buffers to tty_port", the tty buffers are
not freed in some drivers. This is because tty_port_destructor is not
called whenever a tty_port is freed. This was an assumption I counted
with but was unfortunately untrue. So fix the drivers to fulfil this
assumption.

To be sure, the TTY buffers (and later some stuff) are gone along with
the tty_port, we have to call tty_port_destroy at tear-down places.
This is mostly where the structure containing a tty_port is freed.
This patch does exactly that -- put tty_port_destroy at those places.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/kgdb_nmi.c b/drivers/tty/serial/kgdb_nmi.c
index d185247..6ac2b79 100644
--- a/drivers/tty/serial/kgdb_nmi.c
+++ b/drivers/tty/serial/kgdb_nmi.c
@@ -266,6 +266,7 @@
 	}
 	return 0;
 err:
+	tty_port_destroy(&priv->port);
 	kfree(priv);
 	return ret;
 }
@@ -275,6 +276,7 @@
 	struct kgdb_nmi_tty_priv *priv = tty->driver_data;
 
 	tty->driver_data = NULL;
+	tty_port_destroy(&priv->port);
 	kfree(priv);
 }