MINOR: quic: remove TID ref from quic_conn

Remove <tid> member in quic_conn. This is moved to quic_connection_id
instance.

For the moment, this change has no impact. Indeed, qc.tid reference
could easily be replaced by tid as all of this work was already done on
the connection thread. However, it is planified to support quic_conn
thread migration in the future, so removal of qc.tid will simplify this.

This should be backported up to 2.7.
3 files changed