ot::Trel::Interface::Enable() method

Enables the TREL interface. This call initiates an ongoing DNS-SD browse on the service name "_trel._udp" within the local browsing domain to discover other devices supporting TREL. Device also registers a new service to be advertised using DNS-SD, with the service name is "_trel._udp" indicating its support for TREL. Device is ready to receive TREL messages from peers.