Small optimization to MotionProperties::GetInverseInertiaForRotation (#719)

Jolt/Physics/Body/MotionProperties.inl

@@ -60,7 +60,7 @@ Mat44 MotionProperties::GetInverseInertiaForRotation(Mat44Arg inRotation) const
 {
 	JPH_ASSERT(mCachedMotionType == EMotionType::Dynamic);
 
-	Mat44 rotation = inRotation * Mat44::sRotation(mInertiaRotation);
+	Mat44 rotation = inRotation.Multiply3x3(Mat44::sRotation(mInertiaRotation));
 	Mat44 rotation_mul_scale_transposed(mInvInertiaDiagonal.SplatX() * rotation.GetColumn4(0), mInvInertiaDiagonal.SplatY() * rotation.GetColumn4(1), mInvInertiaDiagonal.SplatZ() * rotation.GetColumn4(2), Vec4(0, 0, 0, 1));
 	return rotation.Multiply3x3RightTransposed(rotation_mul_scale_transposed);
 }