Arm backend: add support for operator @

[tirwu01]

Change-Id: Icdc8da1ff7aaa636dff1aeb80442b6e18a8be5fd

Summary

Support @ operator, an equivalent op to torch.matmul.

cc @digantdesai @freddan80 @per @zingo @oscarandersson8218

[pytorch-bot]

🔗 Helpful Links

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❌ 2 New Failures

As of commit 0788343 with merge base cebe051 ():

NEW FAILURES - The following jobs have failed:

• .github/workflows/build-presets.yml (gh)
• pull / android / run-emulator (gh)
  The process '/usr/bin/sh' failed with exit code 255

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[tirwu01]

@pytorchbot label ciflow/trunk

[pytorch-bot]

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[tirwu01]

@per @freddan80 @oscarandersson8218

[pytorch-bot]

To add the ciflow label ciflow/trunk please first approve the workflows that are awaiting approval (scroll to the bottom of this page).

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[tirwu01]

@pytorchbot label "release notes: bug fix"

[pytorch-bot]

Didn't find following labels among repository labels: release notes: bug fix