Discarding malformed Diameter answer

Logged when a peer sends an answer on an Open connection whose framing is valid but whose AVPs cannot be parsed, or a DWA or DPA that fails validation. An answer cannot be answered, so Radiator drops it and keeps the connection open. A request the answer belonged to fails over when its deadline passes; a dropped DWA lets the watchdog treat the peer as unresponsive.

Check the attached error and the logged identifiers against the peer's answer, and correct the peer's message encoding.