QMYSQL: QT application built with libmariadb3.4 won't connect to MariaDB 10

MariaDB 11.4 and (more importantly here) their C connector version 3.4 enable SSL mode by default for all non-local connections as described in https://mariadb.com/kb/en/securing-connections-for-client-and-server/. Support for MYSQL_OPT_SSL_MODE was added as part of QTBUG-84797 but, unfortunately, only for MySQL:

• https://github.com/qt/qtbase/blob/11c171553eece9742ea94196b1cabc85d07d0ffb/src/plugins/sqldrivers/mysql/qsql_mysql.cpp#L1306-L1308 explicitly excludes MariaDB
• also: the docs at https://doc.qt.io/qt-6/sql-driver.html#connection-options unfortunately fail to mention that only MySQL is supported

Without support for this parameter, I can't disable SSL for the MySQL plugin that I'm using from Digikam.

Moreover, even if I'd set up my NAS with SSL, without support for MYSQL_OPT_SSL_VERIFY_SERVER_CERT, I wouldn't be able to connect anyway as I don't have a valid certificate.

Alternatively to implementing custom options could be to provide the ability to pass a custom options file - see https://mariadb.com/kb/en/configuring-mariadb-connectorc-with-option-files/ for details. This may be future-proof and allow all sorts of customisations.