[IPV4]: Make ip_tos2prio const.

Signed-off-by: Philippe De Muyter <phdm@macqel.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 8528502..88fa648 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -167,7 +167,7 @@
 
 #define ECN_OR_COST(class)	TC_PRIO_##class
 
-__u8 ip_tos2prio[16] = {
+const __u8 ip_tos2prio[16] = {
 	TC_PRIO_BESTEFFORT,
 	ECN_OR_COST(FILLER),
 	TC_PRIO_BESTEFFORT,