Client Config Guide improvements (Installation)

[keichwa]

But that chapter is not exclusively for liberty migration. Customers may want to perform a new installation. We remove now important information.

Maybe, a better place for client installation instructions is in the Autoinstallation chapter: https://documentation.suse.com/suma/5.0/en/suse-manager/client-configuration/autoinst-distributions.html. In the clients-*.adoc files we assume the client is up and running, and should now registered to the manager. OTOH, I wouldn't mind add an excursion or appendix to the clients-*.adoc files where we provide basic info about client installation from scratch.

Now we must decide how we should fix the raised issue for the currents releases (5.x and 4.3.x) and then how we want to structure the chapters of the Client Config Guide in general.

Originally posted by @keichwa in #3120 (comment)