I'm not aware of the possibility to restrict this type of maneuver. Nevertheless, you can use truck routing in Here Location Platform for Enterprise, see the documentation here:
It should retrieve much more adapted route for your use case and it might avoid u-turn.
Also, one final simple solution is to calculate route with alternative set to 3 (or make multiple call with other optimizations) and iterates through the different result in order to exclude routes that would include maneuver with a type associated to a u-turn