d/patches: Add patch to disable hardware acceleration
It seems to be broken with recent versions of WebKitGTK, especially on X11. Needs further testing and possibly a bug report against WebKit itself.
This is how it is currently fixed in the upstream version of devhelp: https://gitlab.gnome.org/GNOME/devhelp/-/commit/e6c644683fbb34ac4ceb31150ef20a2536512149