tcp: Fix build warning after tcp_{v4,v6}_init_sock consolidation.

net/ipv4/tcp_ipv4.c: In function 'tcp_v4_init_sock':
net/ipv4/tcp_ipv4.c:1891:19: warning: unused variable 'tp' [-Wunused-variable]
net/ipv6/tcp_ipv6.c: In function 'tcp_v6_init_sock':
net/ipv6/tcp_ipv6.c:1836:19: warning: unused variable 'tp' [-Wunused-variable]
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/tcp_ipv4.c

@@ -1888,14 +1888,13 @@ static const struct tcp_sock_af_ops tcp_sock_ipv4_specific = {
 static int tcp_v4_init_sock(struct sock *sk)
 {
 	struct inet_connection_sock *icsk = inet_csk(sk);
-	struct tcp_sock *tp = tcp_sk(sk);
 
 	tcp_init_sock(sk);
 
 	icsk->icsk_af_ops = &ipv4_specific;
 
 #ifdef CONFIG_TCP_MD5SIG
-	tp->af_specific = &tcp_sock_ipv4_specific;
+	tcp_sk(sk)->af_specific = &tcp_sock_ipv4_specific;
 #endif
 
 	return 0;

net/ipv6/tcp_ipv6.c

@@ -1829,14 +1829,13 @@ static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific = {
 static int tcp_v6_init_sock(struct sock *sk)
 {
 	struct inet_connection_sock *icsk = inet_csk(sk);
-	struct tcp_sock *tp = tcp_sk(sk);
 
 	tcp_init_sock(sk);
 
 	icsk->icsk_af_ops = &ipv6_specific;
 
 #ifdef CONFIG_TCP_MD5SIG
-	tp->af_specific = &tcp_sock_ipv6_specific;
+	tcp_sk(sk)->af_specific = &tcp_sock_ipv6_specific;
 #endif
 
 	return 0;