Add special case for macosx
When using libboost_iostreams below 1.80.0 libzstd is linked explicitly but not found even if installed in /usr/local/lib so we need to add this path to the target properties.
When using libboost_iostreams below 1.80.0 libzstd is linked explicitly but not found even if installed in /usr/local/lib so we need to add this path to the target properties.