[NET]: Move unneeded data to initdata section.

This patch reverts Eric's commit 2b008b0a8e

It diets .text & .data section of the kernel if CONFIG_NET_NS is not set.
This is safe after list operations cleanup.

Signed-of-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/loopback.c

@@ -284,7 +284,7 @@ static __net_exit void loopback_net_exit(struct net *net)
 	unregister_netdev(dev);
 }
 
-static struct pernet_operations loopback_net_ops = {
+static struct pernet_operations __net_initdata loopback_net_ops = {
        .init = loopback_net_init,
        .exit = loopback_net_exit,
 };