- Invoke Python scripts with `python3` if `python` is not available.
Despite SciresM preferring Python 2, the scripts used in the build all
worked in Python 3 already, so this is just a Makefile change.
- Export `MAKE` to work around a GNU bug.
See the comment for details.
- `rmdir --ignore-fail-on-non-empty` -> `rmdir 2>/dev/null`
macOS `rmdir` doesn't support `--ignore-fail-on-non-empty`.
This is a slight downgrade in functionality, because now we ignore all
errors from `rmdir` rather than just 'Directory not empty'. I could
have avoided this with a more complicated fix, but the benefit strikes
me as not worth the complexity. Let me know if you disagree.
- Append `$(DEVKITPRO)/tools/bin/` to `$PATH` when invoking
`build_romfs`.
This avoids the need to add devkitPro directories to `$PATH` when
building Atmosphere.
If you already have `build_romfs` in your PATH, then that will still
take precedence. (This seemed like the nicer option, though I don't
have strong opinions.)
