Fixing error with new policy not available on older CMakes.  https://tracker.physiomeproject.org/show_bug.cgi?id=3726
Fixing error with new policy not available on older CMakes.  https://tracker.physiomeproject.org/show_bug.cgi?id=3726

hsorby/zinc,OpenCMISS/zinc,OpenCMISS/zinc,hsorby/zinc,OpenCMISS/zinc,hsorby/zinc,OpenCMISS/zinc,hsorby/zinc