Since one of the last Tumbleweed snapshots (somewhen between 20210723 and
20210726), /etc/polkit-default-privs.local gets ignored - with the effect that
for example shutdown from KDE no longer works (I use
PERMISSION_SECURITY="secure local" + a few polkit local overrides, one of them
allows shutdown from KDE).

Actually there are two problems in one:
- /etc/polkit-default-privs.local was renamed to
  /etc/polkit-default-privs.local.rpmsave during zypper dup
- renaming it back and running set_polkit_default_privs didn't change/fix 
  anything. set_polkit_default_privs completely ignores 
  /etc/polkit-default-privs.local (confirmed by running it with bash -x)

I don't have a problem with moving the default config to /usr/etc/ - but PLEASE
avoid breaking things while doing so.

(Severity major because it's a regression, and because it breaks shutdown and
some other things for me.)