ipv6: Use correct data types for ICMPv6 type and code

Change all the code that deals directly with ICMPv6 type and code
values to use u8 instead of a signed int as that's the actual data
type.

Signed-off-by: Brian Haley <brian.haley@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 658293e..1473ee0 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -1865,7 +1865,7 @@
  *	Drop the packet on the floor
  */
 
-static int ip6_pkt_drop(struct sk_buff *skb, int code, int ipstats_mib_noroutes)
+static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
 {
 	int type;
 	struct dst_entry *dst = skb_dst(skb);