Postpone broadlink platform switch until config entry is ready

[elupus]

Proposed change

We must setup the platform data with the config entry setup callback,
and device information. So trigger a platform not ready until the entry
has been setup, then use the stored callback function to setup.

The old solution relied on platform setup having completed before config entry setup. This is no longer guaranteed (if it ever was)

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)
• Deprecation (breaking change to happen in the future)
• 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 Custom Broadlink IR/RF Switches not loaded at startup #76297

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[probot-home-assistant]

Hey there @Danielhiversen, @felipediel, @L-I-Am, mind taking a look at this pull request as it has been labeled with an integration (broadlink) you are listed as a code owner for? Thanks!
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[elupus]

This is rather ugly. At some point we need to move the broadlink switches key to under the broadlink top yaml. That would be a breaking change and we do have a regression at the moment, so some type of fix is needed.

If you have some other nicer solutions i'm all ears.

[felipediel]

We could subscribe to EVENT_COMPONENT_LOADED (https://developers.home-assistant.io/docs/integration_listen_events/) in the switch platform.

Thanks for the fix.

[balloob]

If there is a config entry, async_setup_platform shouldn't exist/use anything from it. async_setup_platform either sets up their own stuff independently (if legacy), or it triggers an import and then all is taken care off by the config entry. This hybrid approach should be avoided.

Will merge to fix the current issue, but this should be refactored.

[chriselera]

Confirmed working in 2022.8.2. Thanks!