This ensures compatibility with pkg repo so a change in upstream
doesn't break setup. See:

  https://lists.freebsd.org/pipermail/freebsd-cloud/2020-April/000234.html



Message-Id: <CAKBkRUzicxphjjkkxdgzB3cDSv=AszD5V4X499jT2BjiAaazGw@mail.gmail.com>
Signed-off-by: Li-Wen Hsu <lwhsu@lwhsu.org>
[AJB: applied from Li-Wen's github, applied sob, tweaked commit message]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>