Call wxTopLevelWindow::Layout() rather than DoLayout()

Ideal would be to completely get rid of the DoLayout() method later,
however this method seems to be used in the existing applications, so
for now it needs to be kept.

src/generic/wizard.cpp

@@ -929,7 +929,7 @@ bool wxWizard::DoLayoutAdaptation()
     wxStandardDialogLayoutAdapter::DoFitWithScrolling(this, windows);
 
     // Size event doesn't get sent soon enough on wxGTK
-    DoLayout();
+    Layout();
 
     SetLayoutAdaptationDone(true);