Arm Backend: Add support for expm1.default

[agrima1304]

Decompose expm1 into other operators or use the Taylor series expansion when input values are close to 0.

cc @digantdesai @freddan80 @per @zingo @oscarandersson8218

[pytorch-bot]

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❌ 1 New Failure, 1 Cancelled Job, 1 Unrelated Failure

As of commit 3816878 with merge base 7535720 ():

NEW FAILURE - The following job has failed:

• Build documentation / build (buck2) / Build doc (gh)
  At least one of the pre-conditions you specified did not hold

CANCELLED JOB - The following job was cancelled. Please retry:

• trunk / test-models-macos-cpu (mv3, portable) / macos-job (gh)
  ##[error]The operation was canceled.

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

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

• Apple / build-demo-ios / macos-job (gh) (trunk failure)
  RuntimeError: Command bash /Users/runner/work/_temp/exec_script failed with exit code 65

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[agrima1304]

@pytorchbot label "partner: arm"

[pytorch-bot]

Didn't find following labels among repository labels: partner:arm

[agrima1304]

@pytorchbot label "release notes: arm"

[agrima1304]

@pytorchbot label "partner: arm"

[agrima1304]

@pytorchbot label "ciflow/trunk"

[pytorch-bot]

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