Use XNN fused RoPE for HF-style RoPE patterns

[GregoryComer]

Summary

Pattern match HF style RoPE and delegate to XNNPACK. Relax slice constraints and add unsqueeze, as well, since XNNPACK supports them and it's easiest to not have to conditionally partition them for RoPE only when fusable.

[pytorch-bot]

🔗 Helpful Links

🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/18627

• 📄 Preview Python docs built from this PR

Note: Links to docs will display an error until the docs builds have been completed.

❌ 1 Awaiting Approval, 5 New Failures, 2 Unrelated Failures

As of commit 1594c71 with merge base aa7c8ce ():

AWAITING APPROVAL - The following workflow needs approval before CI can run:

• periodic (gh)

NEW FAILURES - The following jobs have failed:

• Lint / lintrunner-mypy (gh)
  >>> Lint for backends/arm/test/models/stable_diffusion/stable_diffusion_module_test_configs.py:
• pull / test-lora-linux / linux-job (gh)
  RuntimeError: Command docker exec -t b2eed6ec8ffb03f59e6cb5f58a7e3c15196c4521a45c88801ea2f900a8d82517 /exec failed with exit code 1
• pull / test-lora-multimethod-linux / linux-job (gh)
  RuntimeError: Command docker exec -t 0bdfa09045b4b99e3b220930c7e2c7b196323caf8af7ede698a43e36d4233c37 /exec failed with exit code 1
• pull / test-openvino-linux / linux-job (gh)
  RuntimeError: Command docker exec -t 29994ff0d2d3258ab01861c05ad6eed42950d1ad68f111312b500194782c7552 /exec failed with exit code 1
• pull / test-phi-3-mini-runner-linux / linux-job (gh)
  RuntimeError: Command docker exec -t 025ace708c153a4f538573d41b5ed8eca475b25052ba796671f05c54c579c20d /exec failed with exit code 1

BROKEN TRUNK - The following jobs failed but were present on the merge base:

👉 Rebase onto the `viable/strict` branch to avoid these failures

• pull / unittest / windows / windows-job (gh) (trunk failure)
  ##[error]The operation was canceled.
• pull / unittest-editable / windows / windows-job (gh) (trunk failure)
  ##[error]The operation was canceled.

This comment was automatically generated by Dr. CI and updates every 15 minutes.

[github-actions]

This PR needs a release notes: label

If your change should be included in the release notes (i.e. would users of this library care about this change?), please use a label starting with release notes:. This helps us keep track and include your important work in the next release notes.

To add a label, you can comment to pytorchbot, for example
@pytorchbot label "release notes: none"

For more information, see
https://github.com/pytorch/pytorch/wiki/PyTorch-AutoLabel-Bot#why-categorize-for-release-notes-and-how-does-it-work.