Fix cached network address matching for server
Fix cached network address matching for server

Bug in cached address support meant client addresses weren't being cached after each registration request.
This fix should ensure the server will use the same network address instance for all messages to/from client.

Signed-off-by: Rory Latchem <c3c1383852e71bcaf9d2b563b72ae8e3b5303dd9@imgtec.com>

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