Refactor: clean trainer device & distrib getters

[Borda]

What does this PR do?

Fixes # (issue) <- this links related issue to this PR

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[pep8speaks]

Hello @Borda! Thanks for updating this PR.

• In the file pytorch_lightning/accelerators/accelerator_connector.py:

Line 190:13: W503 line break before binary operator
Line 201:13: W503 line break before binary operator

• In the file pytorch_lightning/trainer/connectors/checkpoint_connector.py:

Line 295:21: W503 line break before binary operator

• In the file pytorch_lightning/trainer/training_loop.py:

Line 156:17: W503 line break before binary operator
Line 157:17: W503 line break before binary operator

Comment last updated at 2021-01-12 08:41:03 UTC

[codecov]

Codecov Report

Merging #5300 (79ce3be) into release/1.2-dev (2373858) will increase coverage by 46%.
The diff coverage is 98%.

@@                Coverage Diff                @@
##           release/1.2-dev   #5300     +/-   ##
=================================================
+ Coverage               46%     93%    +46%     
=================================================
  Files                  151     151             
  Lines                10482   10616    +134     
=================================================
+ Hits                  4844    9831   +4987     
+ Misses                5638     785   -4853     

[awaelchli]

@Borda may need some help from you to port these changes properly when we eventually rebase #5385

[awaelchli]

We should make sure we don't use these properties internally otherwise users gets spammed with deprecation warnings and they can't do anything about it.

This already happens in some places with other deprecation warnings and this is very confusing to the user (warning utils)