Add additional information about the -cind option in the README.

[On-JungWoan]

1. Content and background

2. Summary of corrections

Add additional information about the -cind option in the README.md file.

Also, you can use the `-cind` option to specify custom input for `-cotof`, instead of using the default dummy input. Otherwise, all input values will be set to 1. For more information about the `-cind` option, please refer to [here](#cli-parameter).

3. Before/After (If there is an operating log that can be used as a reference)

4. Issue number (only if there is a related issue)

[PINTO0309]

It's very good to have a clearer explanation.