Set ODCs buildinstall_method only when bootable compose is requested. Enable Pungi runroot on stg backend.

inventory/group_vars/odcs-backend-stg

@@ -40,6 +40,7 @@ fedmsg_certs:
   - odcs.compose.state-changed
 
 odcs_allowed_source_types: ["tag", "repo", "raw_config"]
+odcs_pungi_runroot_enabled: True
 odcs_pungi_runroot_packages: ["pungi", "fedora-packager", "python2-modulemd", "python2-pdc-client"]
 odcs_pungi_runroot_tag: f26-build
 odcs_runroot_target_dir_url: http://kojipkgs.stg.fedoraproject.org/compose/odcs

roles/odcs/base/files/pungi.conf

@@ -64,7 +64,9 @@ media_checksums = ['sha256']
 create_jigdo = False
 
 # BUILDINSTALL
+{%- if config.bootable %}
 buildinstall_method="lorax"
+{%- endif %}
 
 skip_phases = [
 {%- if "iso" not in config.results %}