Arm backend: Remove FP specific NodeVisitors

[oscarandersson8218]

Merge NodeVisitors of targets with one FP and one INT visitor. Having two node visitors to choose from makes the INT+FP case tricky, hence why they are being merged.

cc @freddan80 @per @zingo @digantdesai

[pytorch-bot]

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❗ 1 Active SEVs

There are 1 currently active SEVs. If your PR is affected, please view them below:

• ROCm failures during provisioning step due to network issues

❌ 1 New Failure, 1 Cancelled Job, 6 Unrelated Failures

As of commit 4d60df2 with merge base bde6b11 ():

NEW FAILURE - The following job has failed:

• pull / test-llama-runner-qnn-linux (fp32, qnn_16a16w, qnn) / linux-job (gh)
  RuntimeError: Command docker exec -t f5831259b77ab3f3675a59127975fc39d2b3244c68eb7537007d6380e4153935 /exec failed with exit code 1

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

• trunk / test-models-macos-cpu (vit, xnnpack-quantization-delegation) / macos-job (gh)
  ##[error]The operation was canceled.

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

• pull / test-setup-linux-gcc / linux-job (gh) (similar failure)
  ##[error]The operation was 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 / test-binary-size-linux-gcc / linux-job (gh) (trunk failure)
  ##[error]The operation was canceled.
• pull / test-openvino-linux / linux-job (gh) (trunk failure)
  ##[error]The operation was canceled.
• pull / unittest / windows / windows-job (gh) (trunk failure)
  backends/xnnpack/test/ops/test_conv1d.py::TestConv1d::test_qs8_conv1d_batchnorm_seq
• pull / unittest-editable / windows / windows-job (gh) (trunk failure)
  backends/xnnpack/test/ops/test_conv1d.py::TestConv1d::test_qs8_conv1d_batchnorm_seq
• trunk / unittest-release / windows / windows-job (gh) (trunk failure)
  backends/xnnpack/test/ops/test_conv1d.py::TestConv1d::test_qs8_conv1d_batchnorm_seq

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