Treat container subplatforms like main platform
    
    ipa-server-upgrade does not like platform mismatches. Upgrade from an
    old container to recent container fails with error message:
    
    ```
      IPA server upgrade failed: Inspect /var/log/ipaupgrade.log and run command ipa-server-upgrade manually.
      ("Unable to execute IPA upgrade: platform mismatch (expected 'fedora', current 'fedora_container')", 1)
    ```
    
    Upgrade state now treats a container subplatform like its main platform.
    ``fedora_container`` is really a ``fedora`` platform with some paths
    redirected to ``/data`` partition.
    
    The patch also enhances debug logging for installer and upgrader.
    
    Related: https://pagure.io/freeipa/issue/8401
    Signed-off-by: Christian Heimes <cheimes@redhat.com>
    Reviewed-By: Rob Crittenden <rcritten@redhat.com>
    Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>