Update has_len_all_ranks to use Strategy.root_device

[ananthsub]

What does this PR do?

Same motivation as #11734
Part of #11922

Does your PR introduce any breaking changes? If yes, please list them.

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cc @Borda @justusschock @awaelchli @rohitgr7 @ninginthecloud @otaj

[stale]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed in 7 days if no further activity occurs. If you need further help see our docs: https://pytorch-lightning.readthedocs.io/en/latest/generated/CONTRIBUTING.html#pull-request or ask the assistance of a core contributor here or on Slack. Thank you for your contributions.

[stale]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed in 7 days if no further activity occurs. If you need further help see our docs: https://pytorch-lightning.readthedocs.io/en/latest/generated/CONTRIBUTING.html#pull-request or ask the assistance of a core contributor here or on Slack. Thank you for your contributions.

[carmocca]

The CPU test failures are real:

FAILED trainer/properties/test_estimated_stepping_batches.py::test_num_stepping_batches_gpu[trainer_kwargs0-10]
FAILED trainer/properties/test_estimated_stepping_batches.py::test_num_stepping_batches_gpu[trainer_kwargs1-5]
FAILED trainer/properties/test_estimated_stepping_batches.py::test_num_stepping_batches_gpu[trainer_kwargs2-4]
FAILED trainer/properties/test_estimated_stepping_batches.py::test_num_stepping_batches_gpu[trainer_kwargs3-3]
FAILED trainer/properties/test_estimated_stepping_batches.py::test_num_stepping_batches_gpu[trainer_kwargs4-64]

cc @rohitgr7

[rohitgr7]

The CPU test failures are real:

FAILED trainer/properties/test_estimated_stepping_batches.py::test_num_stepping_batches_gpu[trainer_kwargs0-10]
FAILED trainer/properties/test_estimated_stepping_batches.py::test_num_stepping_batches_gpu[trainer_kwargs1-5]
FAILED trainer/properties/test_estimated_stepping_batches.py::test_num_stepping_batches_gpu[trainer_kwargs2-4]
FAILED trainer/properties/test_estimated_stepping_batches.py::test_num_stepping_batches_gpu[trainer_kwargs3-3]
FAILED trainer/properties/test_estimated_stepping_batches.py::test_num_stepping_batches_gpu[trainer_kwargs4-64]

cc @rohitgr7

patched it