mark old seg3d as broken for now since it no longer builds with stock gcc version and flags

(cherry picked from commit f02ac9588f)

pkgs/applications/graphics/seg3d/default.nix

@@ -48,4 +48,8 @@ stdenv.mkDerivation {
   '';
 
   buildInputs = [ cmake wxGTK itk mesa libXft libXext libXi zlib libXmu libuuid ];
+
+  meta = {
+    broken = true;
+  };
 }