Add neutronPowerOn/neutronPowerOff hooks to NeutronBackend

[JakeStevens]

Summary:
To minimize power, the NPU should be turned on and off, per:

https://docs.nxp.com/bundle/AN14700/page/topics/imx_rt700_system_details.html

This relies on SDK code.

Some users may wrap this code for protection.

So, we want two things:

1. (potentially) turnOn -> execute NPU -> turnOff
2. ability to override turnOn/Off implementations

Further, some may want to leave these stubs so that the ET backend does not control it for them.

Differential Revision: D106668625

cc @robert-kalmar @digantdesai @rascani

[pytorch-bot]

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❌ 1 New Failure, 2 Unrelated Failures

As of commit b316aee with merge base acce7cd ():

NEW FAILURE - The following job has failed:

• Test QNN Backend / test-qnn / test-backend-linux (qnn, operators) / linux-job (gh)
  RuntimeError: Command docker exec -t ede08b119e367a05e108b3545975d3bc3960f366d7aa4556211f7c87757d9df8 /exec failed with exit code 92

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

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[meta-codesync]

@JakeStevens has exported this pull request. If you are a Meta employee, you can view the originating Diff in D106668625.

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[JakeStevens]

I see there are neutronSuspend and neutronResume functions in the neutron header. Maybe can just use those instead?