Correcting the right path to mysql log in Fedora 19

The mysql log is wrong in Fedora 19+ pointing to
/var/lib/mysqld.log while the correct is /var/log/mysqld.log.
This make the job fail if you're running Fedora with
mysql.
This error was inserted by
https://review.openstack.org/#/c/55827/

Change-Id: I63dd494f1ae105ad007344dea40936ab283d55a9
Merge "Correcting the right path to mysql log in Fedora 19"