Core: Clarify Callback_VideoCopiedToXFB and FrameUpdate

Source/Core/Core/Core.h

@@ -25,8 +25,8 @@ namespace Core
 bool GetIsThrottlerTempDisabled();
 void SetIsThrottlerTempDisabled(bool disable);
 
-void Callback_VideoCopiedToXFB(bool video_update);
-void FrameUpdate();
+void Callback_FramePresented();
+void Callback_NewField();
 
 enum class State
 {