Apply Debian-stable patch: Fix memory corruption

[h3xx]

Source: https://sources.debian.org/patches/xautolock/1:2.2-5.1/10-fix-memory-corruption.patch/

[l0b0]

Thank you very much for all these patches, @h3xx! This is quite a surprise – I can't even recall why I made this repo over four years ago, other than perhaps wanting to build it myself. My "contribution" is simply making a copy of the original sources, possibly with a vague hope that this great little piece of software might end up with a version history. Since then I've given up on maintaining my own desktop from scratch, so I'm no longer using xautolock. Also, I'm in no way competent to review these patches. I'm familiar with several languages, but I've only touched C for a few days many years back.

In summary, I'm not a contributor, distributor or user. I can't even ask you to take over this project, as I don't even know whether anyone is still maintaining it. I'm going to archive it soon, but if you have any suggestions feel free to let me know here.