message: Update README.md and correct some typo
diff: @@ -27,7 +27,7 @@ but it also creates the two feature crosses.
  # The preprocessing can take 40 minutes to 1 hour based on the system configuration.
  $ cd ../../tools/criteo_script/
  $ bash preprocess.sh wdl 1 1
  -$ cd ../../samples/wdl/
  +$ cd ../../samples/wdl8gpus/
  ```
  2. Build HugeCTR with the instructions on README.md under home directory.
  