message: Update the instruction of init GIT in README.md
diff: @@ -19,8 +19,7 @@ Please find more introductions in our [**HugeCTR User Guide**](docs/hugectr_user
  ## Build ##
  ### Init Git ###
  ```shell
  -$ git submodule init
  -$ git submodule update
  +$ git submodule update --init --recursive
  ```
  ### Build with Release ###
  