qBound: Don't claim it's "equivalent to qMax(min, qMin(val, max))"

While technically true, those don't assert while qBound does,
so it gives you a false sense of security that
qBound(min, val, max) is safe for unsanitized input ranges.

Pick-to: 6.9 6.8 6.5
Change-Id: Ie26f5eba586a3cd2d3e0cd769427f518e1bc92b9
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
Reviewed-by: Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>

src/corelib/global/qminmax.qdoc

@@ -28,8 +28,7 @@
 /*! \fn template <typename T> const T &qBound(const T &min, const T &val, const T &max)
     \relates <QtMinMax>
 
-    Returns \a val bounded by \a min and \a max. This is equivalent
-    to qMax(\a min, qMin(\a val, \a max)).
+    Returns \a val bounded by \a min and \a max.
 
     Example: