Fix OptiX being shown as available on first generation Maxwell GPUs
Fix OptiX being shown as available on first generation Maxwell GPUs

The OptiX kernels are compiled for target "compute_sm_52", which is only available on second
generation Maxwell GPUs, so disable support for older ones.

tangent-opensource/coreBlackbird,tangent-opensource/coreBlackbird,tangent-opensource/coreBlackbird