only mariadb-tokudb-engine-5.5, no mariadb-tokudb-engine

one should be able to install TokuDB deb package with

apt-get install mariadb-tokudb-engine

So, there should be a virtual package mariadb-tokudb-engine that depends on maria-tokudb-engine-5.5, or maria-tokudb-engine-5.5 should be renamed to mariadb-tokudb-engine