Yes, mortgage interest on a second home is allowed as an itemized deduction. If you have a 1098 form for the new home (or the closing statement to show what you paid for points and taxes), you would select to add "another lender" in the 1098 entry section of TurboTax. See the sample screenshot attached.
Below are the steps to be brought to this section of TurboTax:
https://ttlc.intuit.com/replies/4793767