tcp/dccp: tw_timer_handler() is static

tw_timer_handler() is only used from net/ipv4/inet_timewait_sock.c

Fixes: 789f558cfb36 ("tcp/dccp: get rid of central timewait timer")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/inet_timewait_sock.c b/net/ipv4/inet_timewait_sock.c
index 00ec8d5..2ffbd16 100644
--- a/net/ipv4/inet_timewait_sock.c
+++ b/net/ipv4/inet_timewait_sock.c
@@ -170,7 +170,7 @@
 }
 EXPORT_SYMBOL_GPL(__inet_twsk_hashdance);
 
-void tw_timer_handler(unsigned long data)
+static void tw_timer_handler(unsigned long data)
 {
 	struct inet_timewait_sock *tw = (struct inet_timewait_sock *)data;