Augment RETRY validation token

Adds fields to the QUIC RETRY packet validation token:
timestamp, remote_addr, odcid, & rscid.

Also adds functionality to validate the token once returned by the client.

Note that this does not encrypt the token yet.

Also check that the RSCID stored in the RETRY validation
token matches the DCID in the header.

Reviewed-by: Neil Horman <[email protected]>
Reviewed-by: Saša Nedvědický <[email protected]>
Reviewed-by: Matt Caswell <[email protected]>
Reviewed-by: Tomas Mraz <[email protected]>
(Merged from openssl#26048)

Author: andrewkdinh