Remove deprecated empty macro

Change-Id: Ib2a646ee22a7f97dae584e6f068f17378fe2b494
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>

src/corelib/kernel/qtmetamacros.h

@@ -166,9 +166,6 @@ QT_BEGIN_NAMESPACE
 #define QT_TR_FUNCTIONS
 #endif
 
-// ### Qt6: remove
-#define Q_OBJECT_CHECK  /* empty, unused since Qt 5.2 */
-
 #if defined(Q_CC_INTEL)
 // Cannot redefine the visibility of a method in an exported class
 # define Q_DECL_HIDDEN_STATIC_METACALL

tests/auto/corelib/kernel/qmetaobjectbuilder/tst_qmetaobjectbuilder.cpp

@@ -1341,7 +1341,6 @@ class TestObject : public QObject
 {
     // Manually expanded from Q_OBJECT macro
 public:
-    Q_OBJECT_CHECK
     static QMetaObject staticMetaObject;
     virtual const QMetaObject *metaObject() const;
     virtual void *qt_metacast(const char *);