Stream: proxy_ssl_conf_command directive.

Stream: proxy_ssl_conf_command directive.

Similarly to ssl_conf_command, proxy_ssl_conf_command can be used to
set arbitrary OpenSSL configuration parameters as long as nginx is
compiled with OpenSSL 1.0.2 or later, when connecting to upstream
servers with SSL.  Full list of available configuration commands
can be found in the SSL_CONF_cmd manual page
(https://www.openssl.org/docs/man1.1.1/man3/SSL_CONF_cmd.html).