rhashtable: Disable automatic shrinking by default

Introduce a new bool automatic_shrinking to require the
user to explicitly opt-in to automatic shrinking of tables.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/tipc/socket.c

@@ -2297,6 +2297,7 @@ static const struct rhashtable_params tsk_rht_params = {
 	.key_len = sizeof(u32), /* portid */
 	.max_size = 1048576,
 	.min_size = 256,
+	.automatic_shrinking = true,
 };
 
 int tipc_sk_rht_init(struct net *net)