meson_post_install.py's compile step does not honor DESTDIR
In #456 (closed) support was added for meson to run python byte compilation after the installation. However, this does not support DESTDIR.
If one uses DESTDIR, the compile step is run on /usr/pkg/lib/python3.10/site-packages/meld instead of ${DESTDIR}/usr/pkg/lib/python3.10/site-packages/meld - which works, but does not do what it's intended to do, since the former directory usually won't exist.
Please add DESTDIR support for this to meson_post_install.py.