LLVMObfuscator.so missing

compiling using 
```bash
cd build
cmake -G "Ninja" -DLLVM_ENABLE_PROJECTS="clang" \
    -DCMAKE_BUILD_TYPE=Release -DLLVM_TARGETS_TO_BUILD="X86" \
    -DBUILD_SHARED_LIBS=On ../llvm
ninja
```
on macOS does not seem to compile `LLVMObfuscator.so` but anything else