remove unused pimpl method

Source/SenseGloveTracking/Private/SGTracking/SGXRTracker.cpp

@@ -459,7 +459,6 @@ struct FSGXRTracker::FImpl
     FSGXRHandState& GetLeftHandState();
     FSGXRHandState& GetRightHandState();
 
-    void AddKeys();
     void BuildMotionSourceToKeypointMap();
 
     bool CanOutputTrackingData(EControllerHand Hand) const;
@@ -882,7 +881,6 @@ FSGXRTracker::FSGXRTracker(const TSharedRef<FGenericApplicationMessageHandler>&
                                                    static_cast<IMotionController*>(this));
     IModularFeatures::Get().RegisterModularFeature(IOpenXRExtensionPlugin::GetModularFeatureName(),
                                                    static_cast<IOpenXRExtensionPlugin*>(this));
-    Pimpl->AddKeys();
 
     // We're implicitly requiring that the OpenXRPlugin has been loaded and initialized at this point.
     if (!IOpenXRHMDModule::Get().IsAvailable())
@@ -1435,10 +1433,6 @@ FSGXRHandState& FSGXRTracker::FImpl::GetRightHandState()
     return HandStates[1];
 }
 
-void FSGXRTracker::FImpl::AddKeys()
-{
-}
-
 void FSGXRTracker::FImpl::BuildMotionSourceToKeypointMap()
 {
     if (!MotionSourceToKeypointMap.IsEmpty())