tcp: remove redundant SOCK_DONE checks

In both tcp_splice_read() and tcp_recvmsg(), we already test
sock_flag(sk, SOCK_DONE) right before evaluating sk->sk_state,
so "!sock_flag(sk, SOCK_DONE)" is always true.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/tcp.c

@@ -817,8 +817,7 @@ ssize_t tcp_splice_read(struct socket *sock, loff_t *ppos,
 				 * This occurs when user tries to read
 				 * from never connected socket.
 				 */
-				if (!sock_flag(sk, SOCK_DONE))
-					ret = -ENOTCONN;
+				ret = -ENOTCONN;
 				break;
 			}
 			if (!timeo) {
@@ -2042,13 +2041,10 @@ int tcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int nonblock,
 				break;
 
 			if (sk->sk_state == TCP_CLOSE) {
-				if (!sock_flag(sk, SOCK_DONE)) {
-					/* This occurs when user tries to read
-					 * from never connected socket.
-					 */
-					copied = -ENOTCONN;
-					break;
-				}
+				/* This occurs when user tries to read
+				 * from never connected socket.
+				 */
+				copied = -ENOTCONN;
 				break;
 			}