Because `p2p.Server.Name()` function started returning an abbreviated
name of the node this broke the parsing of the name in order to fill in
the labels for `p2p_peers_count` metric, resulting in metrics like this:
```sh
> curl -sS localhost:9090/metrics | grep '^p2p_peers_count'
p2p_peers_count{platform="v0.79.0",type="Statusd",version="unknown"} 3
```
Caused by value returned from `Name()` to look like this:
```
Statusd/v0.79.0/linu...
```
By using `Fullname()` we are sure we are pasing all the segments.
Signed-off-by: Jakub Sokołowski <jakub@status.im>