HDFS-10841. Remove duplicate or unused variable in appendFile(). Contributed by Kihwal Lee.

(cherry picked from commit f6c0b7543f612de756ff0c03e9a2c6e33b496a36)

Conflicts:
	hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSDirAppendOp.java

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSDirAppendOp.java

@@ -84,12 +84,10 @@ final class FSDirAppendOp {
 
     final LocatedBlock lb;
     final FSDirectory fsd = fsn.getFSDirectory();
-    final String src;
     final INodesInPath iip;
     fsd.writeLock();
     try {
       iip = fsd.resolvePathForWrite(pc, srcArg);
-      src = iip.getPath();
       // Verify that the destination does not exist as a directory already
       final INode inode = iip.getLastINode();
       final String path = iip.getPath();