typecode_libmagic_system_provided raises exception when running on Linux armv7l

This exception is raised when running scancode-toolkit on Debian-based distro running on armv7l using the system provided plugins.

The packages 7zip, libmagic1, libmagic-mgc, and libarchive13 have been installed.

```
Exception: libmagic not found. Please refer to the scancode-toolkit documentation on how to install libmagic for your operating system.
```

The exception is caused by https://github.com/aboutcode-org/scancode-plugins/blob/main/builtins/typecode_libmagic_system_provided/src/typecode_libmagic/__init__.py#L58 where the generated path to the libmagic lib directory has the value `/usr/lib/armv7l-linux-gnu`, but the actual path to the libmagic lib directory on the system is `/usr/lib/arm-linux-gnueabihf`.