Only debug log new Sonos SSDP discoveries

[jjlawren]

Proposed change

The new SSDP discovery method provides useful information in the SSDP payloads, but it also prints them every loop. This changes so that we only print the discovery payload the first time we see a speaker, or when it has been re-discovered after being marked away.

If there are intermittent connectivity issues with a speaker we won't see the payloads when they're re-discovered, but I think that's acceptable.

cc: @bdraco

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
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[probot-home-assistant]

Hey there @cgtobi, mind taking a look at this pull request as its been labeled with an integration (sonos) you are listed as a codeowner for? Thanks!
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