HDFS-16312. Fix typo for DataNodeVolumeMetrics and ProfilingFileIoEvents (#3637)

Reviewed-by: Hui Fei <ferhui@apache.org>

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/ProfilingFileIoEvents.java

@@ -80,7 +80,7 @@ class ProfilingFileIoEvents {
     if (isEnabled) {
       DataNodeVolumeMetrics metrics = getVolumeMetrics(volume);
       if (metrics != null) {
-        metrics.addMetadastaOperationLatency(Time.monotonicNow() - begin);
+        metrics.addMetadataOperationLatency(Time.monotonicNow() - begin);
       }
     }
   }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/DataNodeVolumeMetrics.java

@@ -197,7 +197,7 @@ public class DataNodeVolumeMetrics {
       int interval = intervals[i];
       metadataOperationLatencyQuantiles[i] = registry.newQuantiles(
           "metadataOperationLatency" + interval + "s",
-          "Meatadata Operation Latency in ms", "ops", "latency", interval);
+          "Metadata Operation Latency in ms", "ops", "latency", interval);
       dataFileIoLatencyQuantiles[i] = registry.newQuantiles(
           "dataFileIoLatency" + interval + "s",
           "Data File Io Latency in ms", "ops", "latency", interval);
@@ -238,7 +238,7 @@ public class DataNodeVolumeMetrics {
     ms.unregisterSource(name);
   }
 
-  public void addMetadastaOperationLatency(final long latency) {
+  public void addMetadataOperationLatency(final long latency) {
     totalMetadataOperations.incr();
     metadataOperationRate.add(latency);
     for (MutableQuantiles q : metadataOperationLatencyQuantiles) {