mod_turn_external: Fix type of config option (thanks mirux) There was a separate boolean option to enable TLS before, but it was merged with the port number option and it seems the typed API interface got confused. Backport of trunk rev aa7a8aa64d3f

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summary: Allow server administrators to probe any user
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This module lets server administrators send `<presence type="probe"/>`
to any local user and receive their presence in response, bypassing
roster checks.