Add ethos-u and vgf to LLM extension

[Sebastian-Larsson]

cc @freddan80 @per @zingo @oscarandersson8218 @digantdesai @larryliu0820 @mergennachin @cccclai @helunwencser @jackzhxng

[pytorch-bot]

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❌ 8 New Failures, 1 Unrelated Failure

As of commit 1a9d0b6 with merge base 84b4a33 ():

NEW FAILURES - The following jobs have failed:

• pull / test-openvino-linux / linux-job (gh)
  RuntimeError: Command docker exec -t a21f431c2ad7a43a02dbf15cdd3f93de2a7202a2907a482f31d453fbc545936a /exec failed with exit code 1
• pull / unittest / linux / linux-job (gh)
  RuntimeError: Command docker exec -t 68196769e0d22a7a43681240d237bddb509c475e58b60f9356e635f6806bb54b /exec failed with exit code 1
• pull / unittest / macos / macos-job (gh)
  RuntimeError: Command bash /Users/ec2-user/runner/_work/_temp/exec_script failed with exit code 1
• pull / unittest-editable / linux / linux-job (gh)
  RuntimeError: Command docker exec -t ad93979cfc8af2b259d770499dd44be67ce9b6c7cbfb0e97b5fe368d35e9f33f /exec failed with exit code 1
• pull / unittest-editable / macos / macos-job (gh)
  RuntimeError: Command bash /Users/ec2-user/runner/_work/_temp/exec_script failed with exit code 1
• trunk / test-models-macos-coreml (ic4) / macos-job (gh)
  RuntimeError: Command bash /Users/ec2-user/runner/_work/_temp/exec_script failed with exit code 1
• trunk / unittest-release / linux / linux-job (gh)
  RuntimeError: Command docker exec -t 5e88b0aea833b187816b677f54e899b63f56150441df9f23c9397a3aa9148f15 /exec failed with exit code 1
• trunk / unittest-release / macos / macos-job (gh)
  RuntimeError: Command bash /Users/ec2-user/runner/_work/_temp/exec_script failed with exit code 1

UNSTABLE - The following job is marked as unstable, possibly due to flakiness on trunk:

• pull / android / run-emulator (gh) (#16137)
  Timeout waiting for emulator to boot.

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[Sebastian-Larsson]

Let #15556 be merged first and rebase this on top of that.