New review comment by ericonr on void-packages repository

https://github.com/void-linux/void-packages/pull/28277#discussion_r565748833

Comment:
We could maybe expand elf-in-usrshare to other directories, including `/etc`.

On the matter of `/opt`, it's fair to assume most third party stuff will be stripped already, but maybe stuff liked `rpi-userland` still needs to be?