/usr/lib/x86_64-linux-gnu/libhackrf.so is in libhackrf-dev 2015.07.2-11+b2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libhackrf.so.0
/usr/lib/x86_64-linux-gnu/libhackrf.so.0