This commit is two fold.
For one side does a small refactor to move the deletion of custom RPM
macros to package manager level inside a cleaning method. This way only
RPM based package managers run RPM specific code and each package manager
can apply its own specific logic.
On the other hand for the zypper package manager the deletion of
/var/lib/zypp/AnonymousUniqueId file has been added as part of the
new cleaning method.
Fixes#1396
469f71144e