[scripts] Usage-message fix in RNNLM tools (#2623)

Author: ajaech

scripts/rnnlm/prepare_rnnlm_dir.sh

@@ -23,7 +23,7 @@ if [ $# != 3 ]; then
  echo "Usage: $0 [options] <text-dir> <rnnlm-config-dir> <rnnlm-dir>"
  echo "Sets up the directory <rnnlm-dir> for RNNLM training as done by"
  echo "rnnlm/train_rnnlm.sh, and initializes the model."
- echo " <text-dir> is as validated by rnnlm/validate_data_dir.py"
+ echo " <text-dir> is as validated by rnnlm/validate_text_dir.py"
  echo " <rnnlm-config-dir> is as validated by rnnlm/validate_config_dir.sh."
  exit 1
 fi