Previously with HTTPD_SSL_CONFIG_DEFAULT being a MACRO, the
configuration options could not be applied to it. This was casuing
error in multiple scenarios. For e.g., here user_cert_cb is a part
of httpd_ssl_config_t which this macro defines. But the type of
user_cert_cb (esp_tls_server_callback_t) is only available when it is enabled
in esp-tls. The MACRO however cannot be modified to set the defaults
based on configuration option. This fix solves the issue without
breaking the compatibility
- Can be used to get connection or client information (SSL context)
- E.g. Client certificate, Socket FD, Connection state, etc.
- Added example callback for getting client certificate information in 'https_server/simple' example
Closes https://github.com/espressif/esp-idf/issues/7479