devtodo: adjust platforms

devtodo: adjust platforms
unicode: adjust platforms

pkgs/development/tools/devtodo/default.nix

···
     description = "A hierarchical command-line task manager";
     license = licenses.gpl2;
     maintainers = [ maintainers.woffs ];
-    platforms = platforms.all;
+    platforms = platforms.linux;
   };
 }

pkgs/tools/misc/unicode/default.nix

···
     homepage = https://github.com/garabik/unicode;
     license = licenses.gpl3;
     maintainers = [ maintainers.woffs ];
+    platforms = platforms.all;
   };
 }