Reference for tunnel-7807 registration

[cabo]

Comment by @fpalombini

Section 5.2:

+=======+=============+===========================+===========+
| 7807  | tunnel-7807 | Carry RFC 7807 problem    | RFC XXXX  |
|       |             | details in a Concise      |           |
|       |             | Problem Details data item |           |
+-------+-------------+---------------------------+-----------+

Please change the reference to "RFC XXXX, Appendix B".

[cabo]

Closed by ccbbd69