ipv6 sit: Avoid extra need for compat layer in PRL management.

We've introduced extra need of compat layer for ip_tunnel_prl{}
for PRL (Potential Router List) management.  Though compat_ioctl
is still missing in ipv4/ipv6, let's make the interface more
straight-forward and eliminate extra need for nasty compat layer
anyway since the interface is new for 2.6.26.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/if_tunnel.h b/include/linux/if_tunnel.h
index f1fbe9c..d4efe40 100644
--- a/include/linux/if_tunnel.h
+++ b/include/linux/if_tunnel.h
@@ -41,7 +41,7 @@
 	__u16			__reserved;
 	__u32			datalen;
 	__u32			__reserved2;
-	void __user		*data;
+	/* data follows */
 };
 
 /* PRL flags */