[NET_SCHED]: mark classifier ops __read_mostly

Additionally remove unnecessary NULL initilizations of the next pointer.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/cls_route.c b/net/sched/cls_route.c
index 0a8409c..e70edd0 100644
--- a/net/sched/cls_route.c
+++ b/net/sched/cls_route.c
@@ -590,8 +590,7 @@
 	return -1;
 }
 
-static struct tcf_proto_ops cls_route4_ops = {
-	.next		=	NULL,
+static struct tcf_proto_ops cls_route4_ops __read_mostly = {
 	.kind		=	"route",
 	.classify	=	route4_classify,
 	.init		=	route4_init,