HDFS-8579. Update HDFS usage with missing options (Contributed by J.Andreina)

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -983,6 +983,9 @@ Release 2.8.0 - UNRELEASED
     HDFS-8687. Remove the duplicate usage message from Dfsck.java. (Brahma
     Reddy Battula via Arpit Agarwal)
 
+    HDFS-8579. Update HDFS usage with missing options
+    (J.Andreina via vinayakumarb)
+
 Release 2.7.2 - UNRELEASED
 
   INCOMPATIBLE CHANGES

hadoop-hdfs-project/hadoop-hdfs/src/main/bin/hdfs

@@ -26,6 +26,7 @@ function hadoop_usage
   echo "                       Hadoop jar and the required libraries"
   echo "  crypto               configure HDFS encryption zones"
   echo "  datanode             run a DFS datanode"
+  echo "  debug                run a Debug Admin to execute HDFS debug commands"
   echo "  dfs                  run a filesystem command on the file system"
   echo "  dfsadmin             run a DFS admin client"
   echo "  fetchdt              fetch a delegation token from the NameNode"