Fix for mysql.sock and mysql.pid placment

As /etc/init/mysql script is having hardcoced path to resources, recipe
needs to generate proper ones.

On mysql version < 5.5 (SLE11_SP2)

socket --> /var/lib/mysql/mysql.sock
pid_file --> /var/lib/mysql/mysqld.pid

on mysql/mariadb >= 5.5 (OpenSUSE 12.2)