Related to #4448
The only remaining part is filtering out SideroLink addresses when Talos
looks for a node address.
See also https://github.com/talos-systems/siderolink/pull/2
The way to test it out:
```
$ talosctl cluster create ... --extra-boot-kernel-args
siderolink.api=172.20.0.1:4000
```
(where 172.20.0.1 is the bridge IP)
Run `siderolink-agent` (test implementation):
```
$ sudo _out/siderolink-agent-linux-amd64
```
Now on the host, there should be a `siderolink` Wireguard userspace
tunnel:
```
$ sudo wg
interface: siderolink
public key: 2aq/V91QyrHAoH24RK0bldukgo2rWk+wqE5Eg6TArCM=
private key: (hidden)
listening port: 51821
peer: Tyr6C/F3FFLWtnzqq7Dsm54B40bOPq6++PTiD/zqn2Y=
endpoint: 172.20.0.1:47857
allowed ips: fdae:41e4:649b:9303:b6db:d99c:215e:dfc4/128
latest handshake: 2 minutes, 2 seconds ago
transfer: 3.62 KiB received, 1012 B sent
...
```
Each Talos node will be registered as a peer, tunnel is established.
You can now ping Talos nodes from the host over the tunnel:
```
$ ping fdae:41e4:649b:9303:b6db:d99c:215e:dfc4
PING fdae:41e4:649b:9303:b6db:d99c:215e:dfc4(fdae:41e4:649b:9303:b6db:d99c:215e:dfc4) 56 data bytes
64 bytes from fdae:41e4:649b:9303:b6db:d99c:215e:dfc4: icmp_seq=1 ttl=64 time=0.352 ms
64 bytes from fdae:41e4:649b:9303:b6db:d99c:215e:dfc4: icmp_seq=2 ttl=64 time=0.437 ms
```
Signed-off-by: Andrey Smirnov <andrey.smirnov@talos-systems.com>
