SPEC: make '%{pipepath}/private' sssd:sssd owned

Since db1a919 the only socket
in '/private' is an internal SBUS socket.

contrib/sssd.spec.in

@@ -790,7 +790,7 @@ install -D -p -m 0644 contrib/sssd.sysusers %{buildroot}%{_sysusersdir}/sssd.con
 %attr(700,root,root) %dir %{secdbpath}
 %attr(751,%{sssd_user},%{sssd_user}) %dir %{deskprofilepath}
 %attr(775,%{sssd_user},%{sssd_user}) %dir %{pipepath}
-%attr(770,%{sssd_user},root) %dir %{pipepath}/private
+%attr(770,%{sssd_user},%{sssd_user}) %dir %{pipepath}/private
 %attr(775,%{sssd_user},%{sssd_user}) %dir %{pubconfpath}
 %attr(770,%{sssd_user},%{sssd_user}) %dir %{gpocachepath}
 %attr(770,%{sssd_user},%{sssd_user}) %dir %{_var}/log/%{name}