py65: eliminate unneeded meta.platforms

buildPythonApplication already sets meta.platforms to the same set of platforms
supported by Python.

pkgs/misc/emulators/py65/default.nix

@@ -21,6 +21,5 @@ buildPythonApplication rec {
     '';
     license = licenses.bsd3;
     maintainers = with maintainers; [ AndersonTorres ];
-    platforms = with platforms; all;
   };
 }