Zhong Jianxin 0ee24e0b6e python3.pkgs.python-rtmidi: Fix build on darwin ...

When libjack2 enabled on darwin, build fails with error:

```
  ../../src/rtmidi/RtMidi.cpp:3580:5: error: use of undeclared identifier 'sem_timedwait'
      sem_timedwait( &data->sem_cleanup, &ts );
      ^
```

2023-09-08 16:13:31 +02:00

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default.nix

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