Cleanup: Fix build error with clang on windows.

Header and implementation signature for ED_object_add_duplicate
were not the same leading to a build error with clang on windows.

source/blender/editors/include/ED_object.h

@@ -185,7 +185,7 @@ struct Base *ED_object_add_duplicate(struct Main *bmain,
                                      struct Scene *scene,
                                      struct ViewLayer *view_layer,
                                      struct Base *base,
-                                     const uint dupflag);
+                                     const eDupli_ID_Flags dupflag);
 
 void ED_object_parent(struct Object *ob,
                       struct Object *parent,