dccp: constify dccp_create_openreq_child() sock argument

socket no longer needs to be read/write

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/dccp/minisocks.c b/net/dccp/minisocks.c
index 9bfd0dc..d10aace 100644
--- a/net/dccp/minisocks.c
+++ b/net/dccp/minisocks.c
@@ -72,7 +72,7 @@
 	dccp_done(sk);
 }
 
-struct sock *dccp_create_openreq_child(struct sock *sk,
+struct sock *dccp_create_openreq_child(const struct sock *sk,
 				       const struct request_sock *req,
 				       const struct sk_buff *skb)
 {