kernels benchmark does not support XPU

[danielfleischer]

Description

Expected the XPU to be discovered and used for benchmarking for kernels that have XPU versions.

Steps to reproduce

# Will open PR to add kernels[xpu] soon
uv pip install --index  https://download.pytorch.org/whl/xpu "torch==2.12+xpu"

uv pip install "kernels[benchmark]"

source .venv/bin/activate

kernels benchmark kernels-community/flash-attn2 --version 1

Traceback (most recent call last):
  File "/dan/projects/kernels/.venv/bin/kernels", line 10, in <module>
    sys.exit(main())
             ^^^^^^
  File "/dan/projects/kernels/.venv/lib/python3.12/site-packages/kernels/cli/__init__.py", line 87, in main
    args.func(args)
  File "/dan/projects/kernels/.venv/lib/python3.12/site-packages/kernels/cli/__init__.py", line 165, in run_benchmark
    benchmark.run_benchmark(
  File "/dan/projects/kernels/.venv/lib/python3.12/site-packages/kernels/cli/benchmark.py", line 751, in run_benchmark
    results, kernel_sha = run_benchmark_script(
                          ^^^^^^^^^^^^^^^^^^^^^
  File "/dan/projects/kernels/.venv/lib/python3.12/site-packages/kernels/cli/benchmark.py", line 650, in run_benchmark_script
    results, kernel_sha = run_benchmark_class(
                          ^^^^^^^^^^^^^^^^^^^^
  File "/dan/projects/kernels/.venv/lib/python3.12/site-packages/kernels/cli/benchmark.py", line 501, in run_benchmark_class
    setup_fn()
  File "/dan/projects/kernels/.venv/lib/python3.12/site-packages/kernels/benchmarks/attention.py", line 75, in setup_large
    self.q = torch.randn(B, S, H, D, device="cuda", dtype=torch.float16)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/dan/projects/kernels/.venv/lib/python3.12/site-packages/torch/cuda/__init__.py", line 484, in _lazy_init
    raise AssertionError("Torch not compiled with CUDA enabled")

Expected behavior

Measure performance.

Environment

• kernels 0.15.2
• python 3.12.13
• torch 2.12.0+xpu
• triton-xpu 3.7.1
• Linux

Additional context

No response

[sayakpaul]

Cc: @drbh