HDFS-11840. Log HDFS Mover exception message of exit to its own log. Contributed by LiXin Ge.

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/mover/Mover.java

@@ -180,6 +180,7 @@ private ExitStatus run() {
       return ExitStatus.ILLEGAL_ARGUMENTS;
     } catch (IOException e) {
       System.out.println(e + ".  Exiting ...");
+      LOG.error(e + ".  Exiting ...");
       return ExitStatus.IO_EXCEPTION;
     } finally {
       dispatcher.shutdownNow();