Fix and simplify build_local.sh; partially fixes VSTS bug 81
Fix and simplify build_local.sh; partially fixes VSTS bug 81

mitls/hacl-star,mitls/hacl-star,mitls/hacl-star,mitls/hacl-star,mitls/hacl-star,mitls/hacl-star,mitls/hacl-star,mitls/hacl-star,mitls/hacl-star