DarkPlaces on Linux has no icon

[hemebond]

When running DarkPlaces on Linux, there is no DarkPlaces custom icon shown for the running application. Instead one sees this:

It looks like the code that set the icon was removed along with SDL1.2 support in
commit 7165b96

[hemebond]

I'm not sure there is a way to fix this. I've tried to use SDL_SetWindowIcon but it doesn't work and seems to be an issue with the Window Manager; it seems they now/currently prefer a .desktop file to set the icon.