Qt: Remove "What's this" button

Source/Core/DolphinQt2/Config/Mapping/GCPadWiiUConfigDialog.cpp

@@ -15,6 +15,8 @@
 GCPadWiiUConfigDialog::GCPadWiiUConfigDialog(int port, QWidget* parent)
     : QDialog(parent), m_port{port}
 {
+  setWindowFlags(windowFlags() & ~Qt::WindowContextHelpButtonHint);
+
   CreateLayout();
   ConnectWidgets();
 

Source/Core/DolphinQt2/Config/Mapping/IOWindow.cpp

@@ -34,7 +34,9 @@ IOWindow::IOWindow(QWidget* parent, ControllerEmu::EmulatedController* controlle
 {
   CreateMainLayout();
   ConnectWidgets();
+
   setWindowTitle(type == IOWindow::Type::Input ? tr("Configure Input") : tr("Configure Output"));
+  setWindowFlags(windowFlags() & ~Qt::WindowContextHelpButtonHint);
 
   Update();
 }