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/ipv4/raw.c b/net/ipv4/raw.c
index 1d0c97c..36035a0 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -606,12 +606,11 @@
 	sk_common_release(sk);
 }
 
-static int raw_destroy(struct sock *sk)
+static void raw_destroy(struct sock *sk)
 {
 	lock_sock(sk);
 	ip_flush_pending_frames(sk);
 	release_sock(sk);
-	return 0;
 }
 
 /* This gets rid of all the nasties in af_inet. -DaveM */