typo

Author: RuinanGu

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

@@ -85,7 +85,7 @@ class StripedWriter {
     targetIndices = new short[targets.length];
     Preconditions.checkArgument(
             targetIndices.length <= dataBlkNum + parityBlkNum - reconstructor.getNumLiveBlocks(),
-            "Reconstrutcion work gets too much targets.");
+            "Reconstruction work gets too much targets.");
     Preconditions.checkArgument(targetIndices.length <= parityBlkNum,
         "Too much missed striped blocks.");
     initTargetIndices();