[PATCH] prevent oops from read of proc entry for tty drivers

There are /proc handles there setup by proc_tty_register_driver, but there is
no module ownership association, so anything that reads after module unload
will blow.

The trivial fix is to propagate the owner of tty_driver to proc entry.

fs/proc/proc_tty.c

@@ -198,6 +198,7 @@ void proc_tty_register_driver(struct tty_driver *driver)
 		return;
 	ent->read_proc = driver->read_proc;
 	ent->write_proc = driver->write_proc;
+	ent->owner = driver->owner;
 	ent->data = driver;
 
 	driver->proc_entry = ent;