OBJECT_ENTRY_AUTO is not implemented

Newer ATL implementations support OBJECT_ENTRY_AUTO,
which has the advantage that the object itself can stay private.

For example shell32 needs to have all class definitions available in headers just for the ObjectMap:
https://git.reactos.org/?p=reactos.git;a=blob;f=dll/win32/shell32/shell32.cpp;hb=93dface84e940b6de679ef35b56b6101fb8083e6#l273

With OBJECT_ENTRY_AUTO the objects can just be private inside one c++ file, without having to share the types in precompiled headers and whatnot.