lnrpc/peers: skeleton logic for updateNodeAnnouncement

Basic logic for the endpoint:

- Get the current nodeAnn information
- Calculate modifications
- Apply modifications
- Return changes

config.go

@@ -35,6 +35,7 @@ import (
 	"github.com/lightningnetwork/lnd/input"
 	"github.com/lightningnetwork/lnd/lncfg"
 	"github.com/lightningnetwork/lnd/lnrpc"
+	"github.com/lightningnetwork/lnd/lnrpc/peersrpc"
 	"github.com/lightningnetwork/lnd/lnrpc/routerrpc"
 	"github.com/lightningnetwork/lnd/lnrpc/signrpc"
 	"github.com/lightningnetwork/lnd/lnwallet"
@@ -516,6 +517,7 @@ func DefaultConfig() Config {
 		SubRPCServers: &subRPCServerConfigs{
 			SignRPC:   &signrpc.Config{},
 			RouterRPC: routerrpc.DefaultConfig(),
+			PeersRPC:  &peersrpc.Config{},
 		},
 		Autopilot: &lncfg.AutoPilot{
 			MaxChannels:    5,