- Adds a new AVP within a Failed-AVP over an answer message (for requests, do nothing).
- If Failed-AVP AVP doesn't exists, is added and then filled (added within) with the value provided (empty AVP id representantion).
- If Failed-AVP AVP already exists, is filled (added within) with the value provided (empty AVP id representantion).
-
- This method is internally used during #decode and/or #valid procedures in order to build automatic answers, but application
- could call this for set another Failed-AVP content no detected by these methods, for example: DIAMETER_CONTRADICTING_AVPS or
- DIAMETER_INVALID_AVP_BIT_COMBO).