Fix Ubuntu 18 Auditctl check

[okynos]

From our user @zodiacnet we know that Auditctl check is not working at Ubuntu 18 system.

We want to solve this issue as soon as possible by adding a conditional check including different default paths.
In addition, it would be desirable to include an option in the config to set the Auditctl path.

Thanks to @zodiacnet for your feedback and report. It has been a while from the report thanks for your support and understanding.