[IPV6]: Use kmemdup

Code diff stats:

[acme@newtoy net-2.6.20]$ codiff /tmp/ipv6.ko.before /tmp/ipv6.ko.after
/pub/scm/linux/kernel/git/acme/net-2.6.20/net/ipv6/ip6_output.c:
  ip6_output      |  -52
  ip6_append_data |   +2
 2 functions changed, 2 bytes added, 52 bytes removed

/pub/scm/linux/kernel/git/acme/net-2.6.20/net/ipv6/addrconf.c:
  addrconf_sysctl_register |  -27
 1 function changed, 27 bytes removed

/pub/scm/linux/kernel/git/acme/net-2.6.20/net/ipv6/tcp_ipv6.c:
  tcp_v6_syn_recv_sock  |  -32
  tcp_v6_parse_md5_keys |  -24
 2 functions changed, 56 bytes removed

/tmp/ipv6.ko.after:
 5 functions changed, 2 bytes added, 135 bytes removed
[acme@newtoy net-2.6.20]$

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index b41c5d8..a5e8d20 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -3969,10 +3969,9 @@
 	struct addrconf_sysctl_table *t;
 	char *dev_name = NULL;
 
-	t = kmalloc(sizeof(*t), GFP_KERNEL);
+	t = kmemdup(&addrconf_sysctl, sizeof(*t), GFP_KERNEL);
 	if (t == NULL)
 		return;
-	memcpy(t, &addrconf_sysctl, sizeof(*t));
 	for (i=0; t->addrconf_vars[i].data; i++) {
 		t->addrconf_vars[i].data += (char*)p - (char*)&ipv6_devconf;
 		t->addrconf_vars[i].de = NULL;