HDFS-17602. RBF mount point with SPACE order can not find the most available namespace, it will choose an irrelevant namespace

Author: wzk784533

hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/resolver/order/AvailableSpaceResolver.java

@@ -121,6 +121,7 @@ protected String chooseFirstNamespace(String path, PathLocation loc) {
         getSubclusterMapping();
     List<SubclusterAvailableSpace> subclusterList = new LinkedList<>(
         subclusterInfo.values());
+
     if (loc != null && loc.getDestinations() != null) {
         Set<String> locSet = new HashSet<String>();
         for (RemoteLocation dest : loc.getDestinations()) {