[NET]: sk_add_backlog convert from macro to inline

There is no reason for sk_add_backlog to be a macro. It can
just be an inline function and get type checking.
Signed-off-by: NStephen Hemminger <shemminger@osdl.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/net/sock.h

@@ -461,16 +461,16 @@ static inline void sk_stream_free_skb(struct sock *sk, struct sk_buff *skb)
 }
 
 /* The per-socket spinlock must be held here. */
-#define sk_add_backlog(__sk, __skb)				\
-do {	if (!(__sk)->sk_backlog.tail) {				\
-		(__sk)->sk_backlog.head =			\
-		     (__sk)->sk_backlog.tail = (__skb);		\
-	} else {						\
-		((__sk)->sk_backlog.tail)->next = (__skb);	\
-		(__sk)->sk_backlog.tail = (__skb);		\
-	}							\
-	(__skb)->next = NULL;					\
-} while(0)
+static inline void sk_add_backlog(struct sock *sk, struct sk_buff *skb)
+{
+	if (!sk->sk_backlog.tail) {
+		sk->sk_backlog.head = sk->sk_backlog.tail = skb;
+	} else {
+		sk->sk_backlog.tail->next = skb;
+		sk->sk_backlog.tail = skb;
+	}
+	skb->next = NULL;
+}
 
 #define sk_wait_event(__sk, __timeo, __condition)		\
 ({	int rc;							\