/usr/powerpc64le-linux-gnu/lib/libatomic.so.1 is in libatomic1-ppc64el-cross 5.4.0-6ubuntu1~16.04.9cross1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/powerpc64le-linux-gnu/lib/libatomic.so.1.1.0