/usr/lib/gcc-cross/m68k-linux-gnu/6/libobjc.so is in libobjc-6-dev-m68k-cross 6.3.0-18cross1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/gcc-cross/m68k-linux-gnu/6/../../../../m68k-linux-gnu/lib/libobjc.so.4