TurboTax is asking about bank information if you want to import your form 1099-R from your financial institution. But this does not apply to you since you will not be able to import your 1099-R from DFAS.
You can avoid this if you have the form 1099-R in front of you and enter the information yourself instead of importing the form. On the "Let's get your tax info. We’ll help you find and import info from your bank or financial institution" screen scroll down and click on "I'll type it in myself" button. On the next screen select which type of 1099-R you have (and who the form belongs to if you are filing jointly) and click "continue". On the "Enter X's 1099-R" screen enter the information as shown on your 1099-R form.