If the user disables OpenMP, unset the OPENMP_FOUND variable
If the user disables OpenMP, unset the OPENMP_FOUND variable

dariomangoni/chrono,Bryan-Peterson/chrono,hsu/chrono,amelmquist/chrono,hsu/chrono,dariomangoni/chrono,andrewseidl/chrono,amelmquist/chrono,rserban/chrono,tjolsen/chrono,armanpazouki/chrono,rserban/chrono,Bryan-Peterson/chrono,Bryan-Peterson/chrono,tjolsen/chrono,projectchrono/chrono,Milad-Rakhsha/chrono,jcmadsen/chrono,dariomangoni/chrono,dariomangoni/chrono,dariomangoni/chrono,Bryan-Peterson/chrono,amelmquist/chrono,projectchrono/chrono,armanpazouki/chrono,tjolsen/chrono,jcmadsen/chrono,projectchrono/chrono,Milad-Rakhsha/chrono,tjolsen/chrono,andrewseidl/chrono,amelmquist/chrono,hsu/chrono,armanpazouki/chrono,andrewseidl/chrono,amelmquist/chrono,PedroTrujilloV/chrono,armanpazouki/chrono,rserban/chrono,PedroTrujilloV/chrono,Milad-Rakhsha/chrono,armanpazouki/chrono,PedroTrujilloV/chrono,amelmquist/chrono,hsu/chrono,PedroTrujilloV/chrono,jcmadsen/chrono,projectchrono/chrono,jcmadsen/chrono,rserban/chrono,jcmadsen/chrono,Milad-Rakhsha/chrono,armanpazouki/chrono,andrewseidl/chrono,rserban/chrono,Bryan-Peterson/chrono,hsu/chrono,projectchrono/chrono,dariomangoni/chrono,andrewseidl/chrono,jcmadsen/chrono,tjolsen/chrono,Milad-Rakhsha/chrono,jcmadsen/chrono,projectchrono/chrono,Milad-Rakhsha/chrono,rserban/chrono,rserban/chrono,PedroTrujilloV/chrono