[malovpn] change peers.nix address to string without CIDR notation

this way we can easily use ip by hostname in other modules

machines/modules/malobeo/wireguard.nix

@@ -70,7 +70,7 @@ in
       interfaces = {
         malovpn = {
           mtu = 1340; #seems to be necessary to proxypass nginx traffic through vpn
-          address = myPeer.address;
+          address = [ "${myPeer.address}/24" ];
           autostart = cfg.autostart;
           listenPort = mkIf (myPeer.role == "server") myPeer.listenPort;