Fixing DDG4 build & use DD4HEP in a dedicated platform
@rmatev this has been cherry-picked from your branch rm-gong
with a few modifications
Update 13/12/21: pick dd4hep only in the dedicated platform
Edited by Michal Mazurek
@rmatev this has been cherry-picked from your branch rm-gong
with a few modifications
Update 13/12/21: pick dd4hep only in the dedicated platform