[APPLETALK DDP]: Use size_t for size in {send,recv}msg.

net/appletalk/ddp.c

@@ -1552,7 +1552,7 @@ static int ltalk_rcv(struct sk_buff *skb, struct net_device *dev,
 }
 
 static int atalk_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
-			 int len)
+			 size_t len)
 {
 	struct sock *sk = sock->sk;
 	struct atalk_sock *at = at_sk(sk);
@@ -1712,7 +1712,7 @@ static int atalk_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr
 }
 
 static int atalk_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
-			 int size, int flags)
+			 size_t size, int flags)
 {
 	struct sock *sk = sock->sk;
 	struct sockaddr_at *sat = (struct sockaddr_at *)msg->msg_name;