Also:
- vquic-tls.h: do not include unused headers for non-H3 builds.
- autotools: stop looking for `openssl/x509.h` header.
- cmp-config.pl: delete exception for `openssl/x509.h`.
- examples: format/comment sync between the two touched files.
- openssl: drop unused `curlx/wait.h` include.
Closes#20049
a468e605eb