net: Convert wext_pernet_ops

These pernet_operations initialize and purge net::wext_nlevents
queue, and are not touched by foreign pernet_operations.

Mark them async.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/wireless/wext-core.c

@@ -390,6 +390,7 @@ static void __net_exit wext_pernet_exit(struct net *net)
 static struct pernet_operations wext_pernet_ops = {
 	.init = wext_pernet_init,
 	.exit = wext_pernet_exit,
+	.async = true,
 };
 
 static int __init wireless_nlevent_init(void)