/usr/aarch64-linux-gnu/lib/libgomp.so.1 is in libgomp1-arm64-cross 4.8.2-13ubuntu1cross0.11.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/aarch64-linux-gnu/lib/libgomp.so.1.0.0
/usr/aarch64-linux-gnu/lib/libgomp.so.1.0.0