/usr/lib/x86_64-linux-gnu/libMesaOpenCL.so is in mesa-opencl-icd 11.2.0-1ubuntu2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libMesaOpenCL.so.1.0.0
/usr/lib/x86_64-linux-gnu/libMesaOpenCL.so.1.0.0