[NVPTX] Enable OpenCL 3d_image_writes support (#143331)
NV supports opencl_3d_image_writes according
https://developer.nvidia.com/blog/nvidia-is-now-opencl-3-0-conformant/
This PR allows removing explicit enabling of image extensions via
-cl-ext command line option, e.g. at
https://github.com/intel/llvm/blob/43b3d42e2b2060e9e9e3a96469a1982dc4c10ddd/libclc/CMakeLists.txt#L503
