net: constify struct inet6_protocol

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/tunnel6.c b/net/ipv6/tunnel6.c
index 633ad78..51e2832 100644
--- a/net/ipv6/tunnel6.c
+++ b/net/ipv6/tunnel6.c
@@ -133,13 +133,13 @@
 			break;
 }
 
-static struct inet6_protocol tunnel6_protocol = {
+static const struct inet6_protocol tunnel6_protocol = {
 	.handler	= tunnel6_rcv,
 	.err_handler	= tunnel6_err,
 	.flags          = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
 };
 
-static struct inet6_protocol tunnel46_protocol = {
+static const struct inet6_protocol tunnel46_protocol = {
 	.handler	= tunnel46_rcv,
 	.err_handler	= tunnel6_err,
 	.flags          = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,