Backport upstream PR: https://github.com/fedora-sysv/chkconfig/pull/135

From PR description:

ostree container commit wipes /var and thereby erases the data in /var/lib/alternatives; the directory used to store configs/symlinks of alternatives.

/var is not a good place for storing such configs since it won't receive updates on bootc images either. We need to move to another location.

Hence, use /etc/alternatives.admindir when running on an ostree-based system unless /var/lib/alternatives is already present; a user may have worked around the problem. This way we enable alternatives to work on ostree-based systems without breaking backwards compat.

Also see: upstream issue - https://github.com/fedora-sysv/chkconfig/issues/9