Add setup type hints (init)

[epenet]

Breaking change

Proposed change

As spotted in #64313 (CI run https://github.com/home-assistant/core/runs/4851145391?check_suite_focus=true)

This is 100% pure type hints - no code changes.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue:
• Link to documentation pull request:

Checklist

• The code change is tested and works locally.
• Local tests pass. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.
• I have followed the development checklist
• The code has been formatted using Black (black --fast homeassistant tests)
• Tests have been added to verify that the new code works.

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated for www.home-assistant.io

If the code communicates with devices, web services, or third-party tools:

• The manifest file has all fields filled out correctly.
  Updated and included derived files by running: python3 -m script.hassfest.
• New or updated dependencies have been added to requirements_all.txt.
  Updated by running python3 -m script.gen_requirements_all.
• For the updated dependencies - a link to the changelog, or at minimum a diff between library versions is added to the PR description.
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[elupus]

Ok rfxtrx

[epenet]

Are you happy with the latest changes @MartinHjelmare ?

[MartinHjelmare]

It's easier to just commit the suggested changes to guarantee it's done as wanted. That will also resolve the comments automatically.

[epenet]

Agreed. I just got mixed up with the mypy ignore PRs that I'm working on in parallel.
I wanted to test your suggestions locally against mypy but in the end it turns out that xiaomi_miio is still in the mypy ignore list and my testing against mypy was completely pointless!!!

[thecode]

LGTM