ipv6: route templates can be const

We kmemdup() templates, so they can be const.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv6/route.c

@@ -222,7 +222,7 @@ static const u32 ip6_template_metrics[RTAX_MAX] = {
 	[RTAX_HOPLIMIT - 1] = 255,
 };
 
-static struct rt6_info ip6_null_entry_template = {
+static const struct rt6_info ip6_null_entry_template = {
 	.dst = {
 		.__refcnt	= ATOMIC_INIT(1),
 		.__use		= 1,
@@ -242,7 +242,7 @@ static struct rt6_info ip6_null_entry_template = {
 static int ip6_pkt_prohibit(struct sk_buff *skb);
 static int ip6_pkt_prohibit_out(struct sk_buff *skb);
 
-static struct rt6_info ip6_prohibit_entry_template = {
+static const struct rt6_info ip6_prohibit_entry_template = {
 	.dst = {
 		.__refcnt	= ATOMIC_INIT(1),
 		.__use		= 1,
@@ -257,7 +257,7 @@ static struct rt6_info ip6_prohibit_entry_template = {
 	.rt6i_ref	= ATOMIC_INIT(1),
 };
 
-static struct rt6_info ip6_blk_hole_entry_template = {
+static const struct rt6_info ip6_blk_hole_entry_template = {
 	.dst = {
 		.__refcnt	= ATOMIC_INIT(1),
 		.__use		= 1,