Don't check for systemd service
ipaplatform no longer checks for the presence of a systemd service file
to detect the name of the domainname service. Instead it uses osinfo's
version to use the old name on Fedora 28 and the new name on Fedora 29.
This fixes a SELinux violation that prevented httpd from listing systemd
service files.
Fixes: https://pagure.io/freeipa/issue/7661
Signed-off-by: Christian Heimes <cheimes@redhat.com>
Reviewed-By: Rob Crittenden <rcritten@redhat.com>