Fix examples build after a061a64642

Change-Id: I4d10b4439e5a858437751b00efde2bf8c467e857
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

examples/qtconcurrent/imagescaling/imagescaling.cpp

@@ -127,7 +127,7 @@ void Images::open()
         }
     }
 
-    std::function<QImage(const QString&)> scale = [](const QString &imageFileName) {
+    std::function<QImage(const QString&)> scale = [imageSize](const QString &imageFileName) {
         QImage image(imageFileName);
         return image.scaled(QSize(imageSize, imageSize), Qt::IgnoreAspectRatio, Qt::SmoothTransformation);
     };