clean up LG WebOS TV init

[thecode]

Proposed change

Remove duplicated code at init and replace it with coordinator.async_config_entry_first_refresh(), follow up to #177627

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
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• Breaking change (fix/feature causing existing functionality to break)
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Additional information

• This PR fixes or closes issue: fixes #
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