Revert to the old RadianToDegree method

Doesn't seem to be getting called, but prefer to maintain the original behavior to reduce uncertainty.

src/ModelTypes.cpp

@@ -31,19 +31,8 @@ AnimatedTexture::~AnimatedTexture()
 
 RageVector3 RadianToDegree(RageVector3 radian)
 {
-	// This is more accurate than the original SM5 implementation,
+	constexpr float RAD_TO_DEG = 180.0f / PI;
-	// but that raises a double-to-float mismatch warning, so this
+	return radian * RAD_TO_DEG;
-	// prevents that issue from occurring.
-	//
-	// A way to implement the original code exactly would be:
-	//
-	// RageVector3 radian = { radian.x * (180.0f / PI) };
-
-	return RageVector3(
-		static_cast<float>(radian.x * (180.0f / PI)),
-		static_cast<float>(radian.y * (180.0f / PI)),
-		static_cast<float>(radian.z * (180.0f / PI))
-	);
 }
 
 void AnimatedTexture::LoadBlank()