[os-telegraf] Please add CPU temperature monitoring

[broizter]

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• [x] I have searched the existing issues, open and closed, and I'm convinced that mine is new.
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Is your feature request related to a problem? Please describe. The problem I'm having is not being able to monitor CPU temperatures with the Telegraf plugin.

Describe the solution you'd like Add CPU (and possibly other sensors) to the Telegraf plugin. Perhaps like this https://github.com/influxdata/telegraf/blob/master/plugins/inputs/sensors/README.md

Describe alternatives you've considered Using a custom Telegraf config but that is not a very elegant solution.

Additional context No other context.

[aaronntw]

currently the workaround is to edit the telegraf.conf according to this https://forum.opnsense.org/index.php?topic=17938.0

however, the additional line that is added into the telegraf.conf will be removed whenever opnsense is restarted