They are owned by the `setup` package [1], which `pam` requires, so
owning these directories by `pam` is wrong and unnecessary.
Also remove the /run/motd.d line from pamtmp.conf, which is also already
present in the `setup` package's tmpfiles config file.
Should fix warnings like this during package updates:
```
Running scriptlet: libsepol-3.3-2.fc35.x86_64 16/16
/usr/lib/tmpfiles.d/pam.conf:4: Duplicate line for path "/run/motd.d", ignoring.
/usr/lib/tmpfiles.d/setup.conf:2: Duplicate line for path "/run/motd.d", ignoring.
```
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>