QUIC: path revalidation after expansion failure. As per RFC 9000, Section 8.2.1: When an endpoint is unable to expand the datagram size to 1200 bytes due to the anti-amplification limit, the path MTU will not be validated. To ensure that the path MTU is large enough, the endpoint MUST perform a second path validation by sending a PATH_CHALLENGE frame in a datagram of at least 1200 bytes.

# Copyright (C) Igor Sysoev
# Copyright (C) Nginx, Inc.


have=NGX_SUPPRESS_WARN . auto/have

have=NGX_SMP . auto/have