[NETLINK]: Add properly module refcounting for kernel netlink sockets.

- Remove bogus code for compiling netlink as module
- Add module refcounting support for modules implementing a netlink
  protocol
- Add support for autoloading modules that implement a netlink protocol
  as soon as someone opens a socket for that protocol

Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

kernel/audit.c

@@ -514,7 +514,8 @@ static int __init audit_init(void)
 {
 	printk(KERN_INFO "audit: initializing netlink socket (%s)\n",
 	       audit_default ? "enabled" : "disabled");
-	audit_sock = netlink_kernel_create(NETLINK_AUDIT, audit_receive);
+	audit_sock = netlink_kernel_create(NETLINK_AUDIT, audit_receive,
+					   THIS_MODULE);
 	if (!audit_sock)
 		audit_panic("cannot initialize netlink socket");