Remove redundant code to set the device on the LightningModule

[awaelchli]

What does this PR do?

This removes some lines that are no longer needed.
They were originally added in #12985, but then later we decided to set the device earlier in the Trainer: #18021. There are tests for this.

---

📚 Documentation preview 📚: https://pytorch-lightning--19877.org.readthedocs.build/en/19877/

cc @Borda @justusschock @awaelchli

[github-actions]

⚡ Required checks status: All passing 🟢

Groups summary

🟢 pytorch_lightning: Tests workflow

Check ID	Status
pl-cpu (macOS-11, lightning, 3.8, 2.0, oldest)	success	✅
pl-cpu (macOS-11, lightning, 3.10, 2.0)	success	✅
pl-cpu (macOS-11, lightning, 3.10, 2.1)	success	✅
pl-cpu (macOS-11, lightning, 3.10, 2.2)	success	✅
pl-cpu (macOS-14, lightning, 3.10, 2.3)	success	✅
pl-cpu (ubuntu-20.04, lightning, 3.8, 2.0, oldest)	success	✅
pl-cpu (ubuntu-20.04, lightning, 3.10, 2.0)	success	✅
pl-cpu (ubuntu-20.04, lightning, 3.10, 2.1)	success	✅
pl-cpu (ubuntu-20.04, lightning, 3.10, 2.2)	success	✅
pl-cpu (ubuntu-20.04, lightning, 3.10, 2.3)	success	✅
pl-cpu (windows-2022, lightning, 3.8, 2.0, oldest)	success	✅
pl-cpu (windows-2022, lightning, 3.10, 2.0)	success	✅
pl-cpu (windows-2022, lightning, 3.10, 2.1)	success	✅
pl-cpu (windows-2022, lightning, 3.10, 2.2)	success	✅
pl-cpu (windows-2022, lightning, 3.10, 2.3)	success	✅
pl-cpu (macOS-11, pytorch, 3.8, 2.0)	success	✅
pl-cpu (ubuntu-20.04, pytorch, 3.8, 2.0)	success	✅
pl-cpu (windows-2022, pytorch, 3.8, 2.0)	success	✅
pl-cpu (macOS-12, pytorch, 3.11, 2.0)	success	✅
pl-cpu (macOS-12, pytorch, 3.11, 2.1)	success	✅
pl-cpu (ubuntu-22.04, pytorch, 3.11, 2.0)	success	✅
pl-cpu (ubuntu-22.04, pytorch, 3.11, 2.1)	success	✅
pl-cpu (windows-2022, pytorch, 3.11, 2.0)	success	✅
pl-cpu (windows-2022, pytorch, 3.11, 2.1)	success	✅

These checks are required after the changes to src/lightning/pytorch/strategies/deepspeed.py, src/lightning/pytorch/strategies/fsdp.py.

🟢 pytorch_lightning: Azure GPU

Check ID	Status
pytorch-lightning (GPUs) (testing Lightning | latest)	success	✅
pytorch-lightning (GPUs) (testing PyTorch | latest)	success	✅

These checks are required after the changes to src/lightning/pytorch/strategies/deepspeed.py, src/lightning/pytorch/strategies/fsdp.py.

🟢 pytorch_lightning: Benchmarks

Check ID	Status
lightning.Benchmarks	success	✅

These checks are required after the changes to src/lightning/pytorch/strategies/deepspeed.py, src/lightning/pytorch/strategies/fsdp.py.

🟢 pytorch_lightning: Docs

Check ID	Status
docs-make (pytorch, doctest)	success	✅
docs-make (pytorch, html)	success	✅

These checks are required after the changes to src/lightning/pytorch/strategies/deepspeed.py, src/lightning/pytorch/strategies/fsdp.py.

🟢 mypy

Check ID	Status
mypy	success	✅

These checks are required after the changes to src/lightning/pytorch/strategies/deepspeed.py, src/lightning/pytorch/strategies/fsdp.py.

🟢 install

Check ID	Status
install-pkg (ubuntu-22.04, app, 3.8)	success	✅
install-pkg (ubuntu-22.04, app, 3.11)	success	✅
install-pkg (ubuntu-22.04, fabric, 3.8)	success	✅
install-pkg (ubuntu-22.04, fabric, 3.11)	success	✅
install-pkg (ubuntu-22.04, pytorch, 3.8)	success	✅
install-pkg (ubuntu-22.04, pytorch, 3.11)	success	✅
install-pkg (ubuntu-22.04, lightning, 3.8)	success	✅
install-pkg (ubuntu-22.04, lightning, 3.11)	success	✅
install-pkg (ubuntu-22.04, notset, 3.8)	success	✅
install-pkg (ubuntu-22.04, notset, 3.11)	success	✅
install-pkg (macOS-12, app, 3.8)	success	✅
install-pkg (macOS-12, app, 3.11)	success	✅
install-pkg (macOS-12, fabric, 3.8)	success	✅
install-pkg (macOS-12, fabric, 3.11)	success	✅
install-pkg (macOS-12, pytorch, 3.8)	success	✅
install-pkg (macOS-12, pytorch, 3.11)	success	✅
install-pkg (macOS-12, lightning, 3.8)	success	✅
install-pkg (macOS-12, lightning, 3.11)	success	✅
install-pkg (macOS-12, notset, 3.8)	success	✅
install-pkg (macOS-12, notset, 3.11)	success	✅
install-pkg (windows-2022, app, 3.8)	success	✅
install-pkg (windows-2022, app, 3.11)	success	✅
install-pkg (windows-2022, fabric, 3.8)	success	✅
install-pkg (windows-2022, fabric, 3.11)	success	✅
install-pkg (windows-2022, pytorch, 3.8)	success	✅
install-pkg (windows-2022, pytorch, 3.11)	success	✅
install-pkg (windows-2022, lightning, 3.8)	success	✅
install-pkg (windows-2022, lightning, 3.11)	success	✅
install-pkg (windows-2022, notset, 3.8)	success	✅
install-pkg (windows-2022, notset, 3.11)	success	✅

These checks are required after the changes to src/lightning/pytorch/strategies/deepspeed.py, src/lightning/pytorch/strategies/fsdp.py.

---

Thank you for your contribution! 💜

Note
This comment is automatically generated and updates for 60 minutes every 180 seconds. If you have any other questions, contact carmocca for help.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 53%. Comparing base (32e2418) to head (3a2ef75).
Report is 126 commits behind head on master.

❗ There is a different number of reports uploaded between BASE (32e2418) and HEAD (3a2ef75). Click for more details.

HEAD has 514 uploads less than BASE

Flag	BASE (32e2418)	HEAD (3a2ef75)
python3.10	41	12
cpu	147	24
lightning	93	16
pytest	99	2
examples	9	0
app	9	0
lightning_fabric	27	0
python3.11	54	6
python3.8	31	6
gpu	4	2
pytorch_lightning	20	10
pytorch2.0	28	12
pytest-full	52	24
pytorch2.1	11	6
pytorch2.3	6	3
pytorch2.2	7	3
lightning_app	2	0

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #19877      +/-   ##
==========================================
- Coverage      84%      53%     -31%     
==========================================
  Files         426      418       -8     
  Lines       35237    35080     -157     
==========================================
- Hits        29505    18647   -10858     
- Misses       5732    16433   +10701