No CUDAToolkit target for the NVIDIA PTX compiler
Beginning with CUDA 11.1 at the latest - i.e. for several years already- NVIDIA offers a not-driver-based PTX compilation library, libnvptxcompiler (or libnvptxcompiler_static).
Unfortunately, there does not seem to be a target for this library exposed by the CUDAToolkit find script. One should be created.