/usr/lib/gcc-cross/powerpc64le-linux-gnu/8/libtsan.so is in libgcc-8-dev-ppc64el-cross 8-20180414-1ubuntu2cross1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/gcc-cross/powerpc64le-linux-gnu/8/../../../../powerpc64le-linux-gnu/lib/libtsan.so.0