Reviewed-by: Neil Horman <nhorman@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/22673)
**MSST:** Multi-stream single-thread. Refers to a type of multi-stream QUIC
usage in which API calls must not be made concurrently.
+**ODCID:** Original Destination CID. This is the DCID found in the first Initial
+packet sent by a client, and is used to generate the secrets for encrypting
+Initial packets. It is only used temporarily.
+
**PN:** Packet number. Most QUIC packet types have a packet number (PN); see RFC
9000.