unix: remove some pointless conditionals before kfree_skb()

Remove some pointless conditionals before kfree_skb().

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/unix/af_unix.c

@@ -1178,8 +1178,7 @@ out_unlock:
 		unix_state_unlock(other);
 
 out:
-	if (skb)
-		kfree_skb(skb);
+	kfree_skb(skb);
 	if (newsk)
 		unix_release_sock(newsk, 0);
 	if (other)