Fix mysql cookbok for SLE11SP2

1) Hardcode ['mysql']['version'] attribute to 5.5.0 on openSUSE and
   5.0.0 on SLE11. This is only used during my.cnf template generation
   to not put mysql version 5.5.x specific statments onto my.cnf on SLE11
   which is running mysql 5.0.x.
2) innodb_autoinc_lock_mode is mysql 5.5 specific and should be only used
   one openSUSE
3) Fix detection for rhel >= 6 in server attribiutes.