Potentially unnecessary CUDA dependency

[a-gardner1]

In point_to_mesh_distance, a call to torch.cuda.synchronize causes a fatal crash on systems without NVIDIA GPUs installed.

This synchronize call seems redundant since the _unbatched_naive_point_to_mesh_distance only gets called if the inputs are not on a CUDA device.

We encountered this when trying to use the CPU wheel at https://nvidia-kaolin.s3.us-east-2.amazonaws.com/torch-2.8.0_cpu.html in a CI pipeline on a machine without a GPU.

[Caenorst]

Hi @a-gardner1 , good catch! I can't recall why this torch.cuda.synchronize() is here, but I'll try to run CI after removing it.

Thanks!