SSL: silenced warnings when building with OpenSSL 3.0. The OPENSSL_SUPPRESS_DEPRECATED macro is used to suppress deprecation warnings. This covers Session Tickets keys, SSL Engine, DH low level API for DHE ciphers. Unlike OPENSSL_API_COMPAT, it works well with OpenSSL built with no-deprecated. In particular, it doesn't unhide various macros in OpenSSL includes, which are meant to be hidden under OPENSSL_NO_DEPRECATED.