mptcp: Remove unnecessary test for __mptcp_init_sock()

__mptcp_init_sock() always returns 0 because mptcp_init_sock() used
to return the value directly.

But after commit 18b683b ("mptcp: queue data for mptcp level
retransmission"), __mptcp_init_sock() need not return value anymore.

Let's remove the unnecessary test for __mptcp_init_sock() and make
it return void.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/mptcp/protocol.c

@@ -2649,7 +2649,7 @@ static void mptcp_worker(struct work_struct *work)
 	sock_put(sk);
 }
 
-static int __mptcp_init_sock(struct sock *sk)
+static void __mptcp_init_sock(struct sock *sk)
 {
 	struct mptcp_sock *msk = mptcp_sk(sk);
 
@@ -2676,8 +2676,6 @@ static int __mptcp_init_sock(struct sock *sk)
 	/* re-use the csk retrans timer for MPTCP-level retrans */
 	timer_setup(&msk->sk.icsk_retransmit_timer, mptcp_retransmit_timer, 0);
 	timer_setup(&sk->sk_timer, mptcp_timeout_timer, 0);
-
-	return 0;
 }
 
 static void mptcp_ca_reset(struct sock *sk)
@@ -2695,11 +2693,8 @@ static void mptcp_ca_reset(struct sock *sk)
 static int mptcp_init_sock(struct sock *sk)
 {
 	struct net *net = sock_net(sk);
-	int ret;
 
-	ret = __mptcp_init_sock(sk);
-	if (ret)
-		return ret;
+	__mptcp_init_sock(sk);
 
 	if (!mptcp_is_enabled(net))
 		return -ENOPROTOOPT;