Delete nonsense comment

There is nothing called GetInPlaceObject() or SfxInternObject.

Change-Id: Ic2cc48a208874c0781416c77703a5d9fe989519d

sfx2/source/doc/objxtor.cxx

@@ -308,8 +308,6 @@ SfxObjectShell::~SfxObjectShell()
     if ( IsEnableSetModified() )
         EnableSetModified( false );
 
-    // Never call GetInPlaceObject(), the access to the derivative branch
-    // SfxInternObject is not allowed because of a compiler bug
     SfxObjectShell::CloseInternal();
     pImpl->pBaseModel.set( nullptr );