[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/ipv4/ipcomp.c b/net/ipv4/ipcomp.c
index b79cdbe..ae1f45f 100644
--- a/net/ipv4/ipcomp.c
+++ b/net/ipv4/ipcomp.c
@@ -437,7 +437,7 @@
 	goto out;
 }
 
-static struct xfrm_type ipcomp_type = {
+static const struct xfrm_type ipcomp_type = {
 	.description	= "IPCOMP4",
 	.owner		= THIS_MODULE,
 	.proto	     	= IPPROTO_COMP,