Use standard binary multiple unit symbols for game size display.

Use integer math for the calculation as we cannot rely on floats for something as important as game size display!

Source/Core/Common/Src/MathUtil.h

@@ -152,6 +152,28 @@ float MathFloatVectorSum(const std::vector<float>&);
 #define ROUND_UP(x, a)		(((x) + (a) - 1) & ~((a) - 1))
 #define ROUND_DOWN(x, a)	((x) & ~((a) - 1))
 
+template <typename T>
+T Log2(T val)
+{
+#if defined(_M_X64)
+	T result;
+	asm
+	(
+		"bsr %1, %0"
+		: "=r"(result)
+		: "r"(val)
+	);
+	return result;
+#else
+	T result = -1;
+	while (val != 0)
+	{
+		val >>= 1;
+		++result;
+	}
+	return result;
+#endif
+}
 
 // Tiny matrix/vector library.
 // Used for things like Free-Look in the gfx backend.