When moving OpenSSL backend into qtbase/plugins, qopenssl_socket_symbols also moved into openssl plugin. This means qocsp test was temporarily disabled, since it depends heavily on those symbols - in-process test server has to somehow generate a signed OCSP response. To re-enable it, makes sense to provide a minimalistic API within network-private and make ocsp auto-test a private auto-test (the response is, after all, represented by some QByteArray).