Use mysql.service instead of mariadb.service to start MariaDB service on openSUSE

systemctl enable mariadb.service is not working on openSUSE 13.1:

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% sudo systemctl enable mariadb.service
Failed to issue method call: No such file or directory
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Change-Id: I50034a76707259fb9e871e53a8e378dab48ab8fa
Merge "Use mysql.service instead of mariadb.service to start MariaDB service on openSUSE"