HDFS-13667:Typo: Marking all datandoes as stale. Contributed by Nanda Kumar

(cherry picked from commit ccfb816d39878abf4172933327d788c59b9eb082)

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/DatanodeManager.java

@@ -1834,7 +1834,7 @@ public class DatanodeManager {
   }
   
   public void markAllDatanodesStale() {
-    LOG.info("Marking all datandoes as stale");
+    LOG.info("Marking all datanodes as stale");
     synchronized (this) {
       for (DatanodeDescriptor dn : datanodeMap.values()) {
         for(DatanodeStorageInfo storage : dn.getStorageInfos()) {