Description
With the latest changes (I guess commit Spotifyd#1182 f53deb9) the spotifyd does show up as "Librespot" only in Spotify.
This does not matter much if you run one instance. As soon as you run 15, this becomes a problem, because the discovery flow, always discovers another instance an no playback is possible.

To Reproduce

1. Start spotifyd using '--device_name 'TestSpeaker' w/o providing a username and password
2. Ensure the discovery is used
3. Check your Spotify player - you will see a "LibreSpot" instead of "TestSpeaker"

Expected behavior
When a --device_name is given - it should be used in all scenarios, not only with username and password.

Compilation flags

• dbus_mpris
• dbus_keyring
• alsa_backend
• portaudio_backend
• pulseaudio_backend
• rodio_backend

Versions (please complete the following information):

• OS: Debian debian/systemd 241-7~deb10u8
• Spotifyd: 08fedd2
• cargo: 1.66