[Clang] Add `nvptx-arch` tool to query installed NVIDIA GPUs

We already have a tool called `amdgpu-arch` which returns the GPUs on
the system. This is used to determine the default architecture when
doing offloading. This patch introduces a similar tool `nvptx-arch`.
Right now we use the detected GPU at compile time. This is unhelpful
when building on a login node and moving execution to a compute node for
example. This will allow us to better choose a default architecture when
targeting NVPTX. Also we can probably use this with CMake's `native`
setting for CUDA now.

CUDA since 11.6 provides `__nvcc_device_query` which has a similar
function but it is probably better to define this locally if we want to
depend on it in clang.

Reviewed By: tianshilei1992

Differential Revision: https://reviews.llvm.org/D140433