Remove outdated docs for qOverload()

Change-Id: Ie641b1f7100e7053e1fe0299a0b2b0bd708326af
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/doc/snippets/code/src_corelib_global_qglobal.cpp

@@ -621,11 +621,6 @@ template<> class QTypeInfo<A> : public QTypeInfoMerger<A, B, C, D> {};
     ... qOverload<int, const QString &>(&Foo::overloadedFunction)
 //! [52]
 
-//! [53]
-    ... QOverload<>::of(&Foo::overloadedFunction)
-    ... QOverload<int, const QString &>::of(&Foo::overloadedFunction)
-//! [53]
-
 //! [54]
     struct Foo {
         void overloadedFunction(int, const QString &);

src/corelib/global/qoverload.qdoc

@@ -14,16 +14,6 @@
     If a member function is also const-overloaded \l qConstOverload and
     \l qNonConstOverload need to be used.
 
-    qOverload() requires C++14 enabled. In C++11-only code, the helper
-    classes QOverload, QConstOverload, and QNonConstOverload can be used directly:
-
-    \snippet code/src_corelib_global_qglobal.cpp 53
-
-    \note Qt detects the necessary C++14 compiler support by way of the feature
-    test recommendations from
-    \l{https://isocpp.org/std/standing-documents/sd-6-sg10-feature-test-recommendations}
-    {C++ Committee's Standing Document 6}.
-
     \sa qConstOverload(), qNonConstOverload(), {Differences between String-Based
     and Functor-Based Connections}
 */