General: Apply the const specifier where applicable

Source/Core/Core/FifoPlayer/FifoDataFile.h

@@ -67,7 +67,7 @@ public:
 
 	void AddFrame(const FifoFrameInfo &frameInfo);
 	const FifoFrameInfo &GetFrame(u32 frame) const { return m_Frames[frame]; }
-	u32 GetFrameCount() { return static_cast<u32>(m_Frames.size()); }
+	u32 GetFrameCount() const { return static_cast<u32>(m_Frames.size()); }
 
 	bool Save(const std::string& filename);