net: spread __net_init, __net_exit

__net_init/__net_exit are apparently not going away, so use them
to full extent.

In some cases __net_init was removed, because it was called from
__net_exit code.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/sysctl_net_ipv6.c b/net/ipv6/sysctl_net_ipv6.c
index c690736..f841d93 100644
--- a/net/ipv6/sysctl_net_ipv6.c
+++ b/net/ipv6/sysctl_net_ipv6.c
@@ -55,7 +55,7 @@
 };
 EXPORT_SYMBOL_GPL(net_ipv6_ctl_path);
 
-static int ipv6_sysctl_net_init(struct net *net)
+static int __net_init ipv6_sysctl_net_init(struct net *net)
 {
 	struct ctl_table *ipv6_table;
 	struct ctl_table *ipv6_route_table;
@@ -98,7 +98,7 @@
 	goto out;
 }
 
-static void ipv6_sysctl_net_exit(struct net *net)
+static void __net_exit ipv6_sysctl_net_exit(struct net *net)
 {
 	struct ctl_table *ipv6_table;
 	struct ctl_table *ipv6_route_table;