p11: allow p11_child to run completely unprivileged To only operation of p11_child which requires special privileges is the communication to pcscd which handles the Smartcard access. pcscd uses policy-kit for access control so access can easily be configured by dropping config snippets into the right directory. If SSSD is configured to run as un-privileged user this patch creates the needed config snippet for policy-kit and installs it in a suitable directory. As a result p11_child does not have to be installed with SETUID or SETGID bits set. Resolves https://fedorahosted.org/sssd/ticket/2755 by making it obsolete Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>