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/tunnel6.c b/net/ipv6/tunnel6.c
index 669f280..633ad789 100644
--- a/net/ipv6/tunnel6.c
+++ b/net/ipv6/tunnel6.c
@@ -124,7 +124,7 @@
 }
 
 static void tunnel6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
-			int type, int code, int offset, __be32 info)
+			u8 type, u8 code, int offset, __be32 info)
 {
 	struct xfrm6_tunnel *handler;