Move push to talk bindings to overlaycontroller

The old system used the old OpenVR input system which is
incompatible with the new IVRInput.

This change broke the AccessbilityTabController, but
that is to be removed because the functionality can be
found elsewhere.

src/tabcontrollers/AudioTabController.h

@@ -87,7 +87,7 @@ private:
     void onPttStop() override;
     void onPttEnabled() override;
     void onPttDisabled() override;
-    bool pttChangeValid() override;
+
     virtual vr::VROverlayHandle_t getNotificationOverlayHandle() override
     {
         return m_ulNotificationOverlayHandle;
@@ -114,6 +114,8 @@ public:
 
     void eventLoopTick();
 
+    bool pttChangeValid() override;
+
     int playbackDeviceIndex() const;
 
     int mirrorDeviceIndex() const;