tcp: fix tcp_default_init_rwnd() for 4.1

Change-Id: If3ecf5f59acf379ffcc468f28434830a92b0383d
Signed-off-by: Dmitry Shmidt <dimitrysh@google.com>
diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
index d9bce1c..0f3a9d7 100644
--- a/net/ipv4/sysctl_net_ipv4.c
+++ b/net/ipv4/sysctl_net_ipv4.c
@@ -152,7 +152,7 @@
 }
 
 /* Validate changes from /proc interface. */
-static int proc_tcp_default_init_rwnd(ctl_table *ctl, int write,
+static int proc_tcp_default_init_rwnd(struct ctl_table *ctl, int write,
 				      void __user *buffer,
 				      size_t *lenp, loff_t *ppos)
 {