sdl2-compat: simplify doCheck logic

`stdenv.mkDerivation` already checks whether the build platform can
execute host code and disables tests if it's not supported, no need to
duplicate this logic. `doCheck` can be disabled with `overrideAttrs`, no
need for a dedicated override flag.

pkgs/by-name/sd/sdl2-compat/package.nix

@@ -16,7 +16,6 @@
   testers,
   libX11,
   libGL,
-  testSupport ? true,
 }:
 
 stdenv.mkDerivation (finalAttrs: {
@@ -60,7 +59,7 @@ stdenv.mkDerivation (finalAttrs: {
   # skip timing-based tests as those are flaky
   env.SDL_TESTS_QUICK = 1;
 
-  doCheck = testSupport && stdenv.buildPlatform.canExecute stdenv.hostPlatform;
+  doCheck = true;
 
   patches = [ ./find-headers.patch ];
   setupHook = ./setup-hook.sh;