tunnel: fix RFC number in comment for INET_ECN_decapsulate()
tunnel: fix RFC number in comment for INET_ECN_decapsulate()

The quoted text and figure are from RFC 6040 ("Tunnelling of Explicit
Congestion Notification").

Signed-off-by: Neal Cardwell <58d301c70203188c35d379474c26c9cc0636a189@google.com>
Signed-off-by: David S. Miller <fe08d3c717adf2ae63592e4c9aec6e3e404d8e3e@davemloft.net>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs