chore(CMakeLists): add target to build olean files for leanpkg
chore(CMakeLists): add target to build olean files for leanpkg

leanprover/lean,avigad/lean,digama0/lean,fpvandoorn/lean,dselsam/lean,johoelzl/lean,johoelzl/lean,fpvandoorn/lean,leanprover/lean,dselsam/lean,rlewis1988/lean,leanprover/lean,leanprover-community/lean,dselsam/lean,leodemoura/lean,leanprover/lean,avigad/lean,Kha/lean,leanprover-community/lean,Kha/lean,leodemoura/lean,rlewis1988/lean,leanprover/lean,dselsam/lean,fpvandoorn/lean,rlewis1988/lean,Kha/lean,dselsam/lean,leodemoura/lean,leodemoura/lean,Kha/lean,fpvandoorn/lean,rlewis1988/lean,digama0/lean,digama0/lean,leanprover-community/lean,leodemoura/lean,dselsam/lean,johoelzl/lean,johoelzl/lean,leodemoura/lean,johoelzl/lean,leanprover-community/lean,Kha/lean,leanprover-community/lean,avigad/lean,digama0/lean,rlewis1988/lean,digama0/lean,leanprover/lean,johoelzl/lean,Kha/lean,rlewis1988/lean,leanprover-community/lean,avigad/lean,avigad/lean,fpvandoorn/lean,digama0/lean,avigad/lean,fpvandoorn/lean