If the value on your 1099INT is blank, just click on the "x" in the warning box in the TurboTax software message notice demanding a value for that box. The software will then not require an entry, so you can just submit the webpage as blank.
The above answer appeared to work for me, but after that step TurboTax's QA check re-flagged this as and error, so that I was eventually forced to just pick a state (my state of residency).
