[XFRM]: constify 'struct xfrm_type'

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/ipcomp6.c b/net/ipv6/ipcomp6.c
index 710325e..b900395 100644
--- a/net/ipv6/ipcomp6.c
+++ b/net/ipv6/ipcomp6.c
@@ -453,7 +453,7 @@
 	goto out;
 }
 
-static struct xfrm_type ipcomp6_type =
+static const struct xfrm_type ipcomp6_type =
 {
 	.description	= "IPCOMP6",
 	.owner		= THIS_MODULE,