MariaDB upgrade

You can still use the older version by setting like the following in your software release.

[mariadb]
<= mariadb-10.4

TODO (in another merge request...):

• drop deprecated options in my.cnf.in like innodb_locks_unsafe_for_binlog, innodb_file_per_table based on MariaDB version
• support tuning I/O using newly introduced options like innodb_data_file_write_through, innodb_log_file_write_through, innodb_data_file_buffering, innodb_log_file_buffering based on MariaDB version
• [ ] change default collation-server to utf8mb4_uca1400_ai_ci for MariaDB >= 11.5