loongson/pypi: links for bgdist2020

loongson/mirror BGdist2020-0.4.tar.gz
loongson/mirror BGdist2020-0.4-py3-none-any.whl
loongson/mirror BGdist2020-0.3.tar.gz
loongson/mirror BGdist2020-0.3-py3-none-any.whl
loongson/mirror BGdist2020-0.2.tar.gz