config: add sync freelist cli flag

config.go

@@ -234,6 +234,7 @@ type config struct {
 	LndDir          string   `long:"lnddir" description:"The base directory that contains lnd's data, logs, configuration file, etc."`
 	ConfigFile      string   `short:"C" long:"configfile" description:"Path to configuration file"`
 	DataDir         string   `short:"b" long:"datadir" description:"The directory to store lnd's data within"`
+	SyncFreelist    bool     `long:"sync-freelist" description:"Whether the databases used within lnd should sync their freelist to disk. This is disabled by default resulting in improved memory performance during operation, but with an increase in startup time."`
 	TLSCertPath     string   `long:"tlscertpath" description:"Path to write the TLS certificate for lnd's RPC and REST services"`
 	TLSKeyPath      string   `long:"tlskeypath" description:"Path to write the TLS private key for lnd's RPC and REST services"`
 	TLSExtraIPs     []string `long:"tlsextraip" description:"Adds an extra ip to the generated certificate"`