Support for batched matmul

[DrJessop]

Summary: Matmul was relying on linear infra which didn't support batched second argument. This adds support.

Differential Revision: D84279595

[pytorch-bot]

🔗 Helpful Links

🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/14956

• 📄 Preview Python docs built from this PR

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

❗ 2 Active SEVs

There are 2 currently active SEVs. If your PR is affected, please view them below:

• Macos CI runners unavailable
• [ROCm][CI] Machines under the label linux.rocm.gpu.2 are undergoing maintenance.

❌ 5 New Failures, 4 Unrelated Failures

As of commit fa22fd2 with merge base 09eac16 ():

NEW FAILURES - The following jobs have failed:

• pull / test-qnn-wheel-packages-linux (3.10) / linux-job (gh)
  RuntimeError: Command docker exec -t c707b8e0c2fe06335ea1f9a5d1e09724386f109b39f7b3ba6be6cd5ff2d493f1 /exec failed with exit code 1
• pull / test-qnn-wheel-packages-linux (3.11) / linux-job (gh)
  RuntimeError: Command docker exec -t 3d6815a7cf5776e2495ab761473bfe2cfda699216a00d9ba65689015b66fcdce /exec failed with exit code 1
• pull / test-qnn-wheel-packages-linux (3.12) / linux-job (gh)
  RuntimeError: Command docker exec -t 8d3e0b1b39b80207b64ca7ff485f0aa7d2fa06ba5ba0daaea1c04a63c027c24f /exec failed with exit code 1
• pull / test-samsung-models-linux / linux-job (gh)
  RuntimeError: Command docker exec -t efba14cb617c49e9eed3509cb09cf9fa3fc20d797ee9a3f0f385757730d78b2a /exec failed with exit code 1
• Test CUDA Builds / export-voxtral-cuda-artifact / linux-job (gh)
  RuntimeError: Command docker exec -t 5d429b1818270aea209f9ead8b23d7fdf9b09d916891947479af670e25eb4ee9 /exec failed with exit code 2

FLAKY - The following job failed but was likely due to flakiness present on trunk:

• pull / unittest-arm-backend-with-no-fvp (test_pytest_models) / linux-job (gh) (matched linux rule in flaky-rules.json)
  The runner has received a shutdown signal. This can happen when the runner service is stopped, or a manually started runner is canceled.

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

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

• pull / unittest / macos / macos-job (gh) (trunk failure)
• pull / unittest-buck / macos / macos-job (gh) (trunk failure)
• pull / unittest-editable / macos / macos-job (gh) (trunk failure)

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

[meta-codesync]

@DrJessop has exported this pull request. If you are a Meta employee, you can view the originating Diff in D84279595.

[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.

[davorchap]

batched matmul :)