support musl or make universal builds

```
Could not open library '/usr/local/bundle/gems/pyroscope-0.5.12-x8664-linux/lib/rbspy/rbspy.so': Error loading shared library ld-linux-x86-64.so.2: No such file or directory (needed by /usr/local/bundle/gems/pyroscope-0.5.12-x8664-linux/lib/rbspy/rbspy.so). (LoadError)
```
