Add two new workers for NVPTX builders.
There is two workers, the first one is running on Ubuntu Linux 22.04 LTS and the second on is running on Windows Server hosts.
Also added the following NVPTX target builders:
- llvm-nvptx-nvidia-ubuntu
- llvm-nvptx64-nvidia-ubuntu
- llvm-nvptx-nvidia-win
- llvm-nvptx64-nvidia-win