Create systemd drop-in directory on package installation like mariadb-server does

On package installation on systemd based linux distributions the mariadb-server package creates a /etc/systemd/system/mariadb.service.d/ drop-in directory along with the mariadb.service file, in which additional drop-in configuration files can be placed to modify systemd service settings without touching the mariadb.service distribution file itself.

The same is possible for the maxscale.service, but the maxscale package does not create the maxscale.service.d directory up front, it has to be created manually by the user.

IMHO it would be nice if this was consistently implemented between the mariadb and maxscale server packages, having both of then create the drop-in directory up front.