Fixed typo

One line was forgotten during MySQL->MariaDB rename, which caused
failures for deployments when MariaDB should be installed
on separate host.

Change-Id: I5b4268868c0f811d9d4aca96aabb4ea120a86285
Fixes: rhbz#1150348
(cherry picked from commit e18a706c99f2b5ce393fbb31aaf97eb1a891ef02)