Revert "Provide better error if min (or max) is defined in QDateTime"

This reverts commit d0804ff2dd.

The commit breaks JSC which is used by QtWebKit, QtScript and
indirectly by QtQuick1, which blocks integration stable->dev.
JSC should be fixed upstream, but until then we need to revert
the change.

Change-Id: I3f7b8be08b68181e08422d2cb00d7cd70a7fc07f
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Reviewed-by: Thorbjørn Lund Martsum <tmartsum@gmail.com>
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@digia.com>

src/corelib/tools/qdatetime.h

@@ -118,9 +118,6 @@ QT_DEPRECATED inline bool setYMD(int y, int m, int d)
     inline qint64 toJulianDay() const { return jd; }
 
 private:
-#if defined(min) || defined(max)
-#error min or max defined, cannot continue. If this is caused by an #include of windows.h, NOMINMAX can be defined.
-#endif
     static inline qint64 nullJd() { return std::numeric_limits<qint64>::min(); }
     static inline qint64 minJd() { return Q_INT64_C(-784350574879); }
     static inline qint64 maxJd() { return Q_INT64_C( 784354017364); }