etcd: remove (unused) etcd root bucket prefix

This commit removes the unused prefix from the etcd backend config as
etcd key space separation in LND is implemented by using namespaces
instead.

lncfg/db.go

@@ -73,8 +73,8 @@ type DatabaseBackends struct {
 // GetBackends returns a set of kvdb.Backends as set in the DB config.  The
 // local database will ALWAYS be non-nil, while the remote database will only
 // be populated if etcd is specified.
-func (db *DB) GetBackends(ctx context.Context, dbPath string,
-	networkName string) (*DatabaseBackends, error) {
+func (db *DB) GetBackends(ctx context.Context, dbPath string) (
+	*DatabaseBackends, error) {
 
 	var (
 		localDB, remoteDB kvdb.Backend
@@ -88,10 +88,7 @@ func (db *DB) GetBackends(ctx context.Context, dbPath string,
 				db.Etcd.EmbeddedPeerPort,
 			)
 		} else {
-			// Prefix will separate key/values in the db.
-			remoteDB, err = kvdb.GetEtcdBackend(
-				ctx, networkName, db.Etcd,
-			)
+			remoteDB, err = kvdb.GetEtcdBackend(ctx, db.Etcd)
 		}
 		if err != nil {
 			return nil, err