btanks: fix build
commit 7aeac03 (PR #386495) dropped libX11 and libGLU from propagatedBuildInputs in SDL_compat, and #389106 pointed SDL to SDL_compat, which broke this buildHydra fail: https://hydra.nixos.org/build/292729441
Grimmauld 10 months ago 57988f96 2341cd6a