l2tp: tweak exports for l2tp_recv_common and l2tp_ioctl

All of the l2tp subsystem's exported symbols are exported using
EXPORT_SYMBOL_GPL, except for l2tp_recv_common and l2tp_ioctl.

These functions alone are not useful without the rest of the l2tp
infrastructure, so there's no practical benefit to these symbols using a
different export policy.

Change these exports to use EXPORT_SYMBOL_GPL for consistency with the
rest of l2tp.

Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/l2tp/l2tp_core.c

@@ -808,7 +808,7 @@ discard:
 	atomic_long_inc(&session->stats.rx_errors);
 	kfree_skb(skb);
 }
-EXPORT_SYMBOL(l2tp_recv_common);
+EXPORT_SYMBOL_GPL(l2tp_recv_common);
 
 /* Drop skbs from the session's reorder_q
  */

net/l2tp/l2tp_ip.c

@@ -597,7 +597,7 @@ int l2tp_ioctl(struct sock *sk, int cmd, unsigned long arg)
 
 	return put_user(amount, (int __user *)arg);
 }
-EXPORT_SYMBOL(l2tp_ioctl);
+EXPORT_SYMBOL_GPL(l2tp_ioctl);
 
 static struct proto l2tp_ip_prot = {
 	.name		   = "L2TP/IP",