net: change proto destroy method to return void

Change struct proto destroy function pointer to return void.  Noticed
by Al Viro.

Signed-off-by: Brian Haley <brian.haley@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index 350457c..3ce8d2f 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -371,7 +371,7 @@
 
 EXPORT_SYMBOL(inet6_release);
 
-int inet6_destroy_sock(struct sock *sk)
+void inet6_destroy_sock(struct sock *sk)
 {
 	struct ipv6_pinfo *np = inet6_sk(sk);
 	struct sk_buff *skb;
@@ -389,8 +389,6 @@
 
 	if ((opt = xchg(&np->opt, NULL)) != NULL)
 		sock_kfree_s(sk, opt, opt->tot_len);
-
-	return 0;
 }
 
 EXPORT_SYMBOL_GPL(inet6_destroy_sock);