libct/cg/fs: document path removal
libct/cg/fs: document path removal

This is already documented but I guess more explanations (in particular,
why the path is being removed from paths) won't hurt.

Signed-off-by: Kir Kolyshkin <3a017b8ddb3f9cf3e4a59978b004111bdeb97f08@gmail.com>

rhatdan/runc,opencontainers/runc,opencontainers/runc,rhatdan/runc,kolyshkin/runc,rhatdan/runc,kolyshkin/runc,opencontainers/runc,kolyshkin/runc,opencontainers/runc,rhatdan/runc,kolyshkin/runc