Colerar

Unable to build on x86 macOS using LLVM 17.0.6

4

```bash ~/Developer/blst master ❯ bash build.sh + /usr/local/opt/llvm/bin/clang -O2 -fno-builtin -fPIC -Wall -Wextra -Werror -D__ADX__ -c ./src/server.c + /usr/local/opt/llvm/bin/clang -O2 -fno-builtin -fPIC -Wall -Wextra -Werror -D__ADX__ -c ./build/assembly.S /var/folders/x9/jkf9hx9j0y31j5b27wzjx1pr0000gp/T/assembly-ef5665.s:1526:1: error:...

This PR make `CMAKE_INSTALL_PREFIX` environment variable working as expected instead of installing `/lib` to hard-coded `/usr/lib`.

esp. for Rust binary, need to investigate why

## Ref https://llvm.org/docs/ExceptionHandling.html