[openssl/openssl] ca7116: Only take note of the ack deadline if we can actua...

[Matt Caswell]

  Branch: refs/heads/master
  Home:   https://github.com/openssl/openssl
  Commit: ca711651c19530b54f0dd6f7ff6b24b5c8d016a2
      https://github.com/openssl/openssl/commit/ca711651c19530b54f0dd6f7ff6b24b5c8d016a2
  Author: Matt Caswell <matt at openssl.org>
  Date:   2023-06-14 (Wed, 14 Jun 2023)

  Changed paths:
    M ssl/quic/quic_channel.c

  Log Message:
  -----------
  Only take note of the ack deadline if we can actually issue an ack

When determining the next tick deadline we cannot actually issue an
ack if the CC will not let us, or the enc_level is not yet provisioned.

This avoids a bug where we can end up in a busy loop because the next
event deadline is reported as "now" because we want to send an ack, but
we can't actually send anything yet.

Reviewed-by: Tomas Mraz <tomas at openssl.org>
Reviewed-by: Hugo Landau <hlandau at openssl.org>
Reviewed-by: Paul Dale <pauli at openssl.org>
(Merged from https://github.com/openssl/openssl/pull/21181)