Add identifiers for Battery Doorbell Plus / Pro lineup

[hkoci]

Hi, I will leave an issue here for the next maintainer, because my PR went stale.

I no longer use the official Ring integration in Home Assistant rather the MQTT unofficial add-on now, although, it would be nice to have the new Ring lineup model identifiers shown correctly on HA.

I have produced a quick and dirty PR to add these as new variables and it went stale #480.

These are the names of the new lineup;

Codename	Model
cocoa_doorbell_v2	Battery Doorbell Plus
cocoa_doorbell_v3	Battery Doorbell Pro