Yes you can take baby milk through airport security to feed your baby.
The TSA will allow you to bring baby milk or formula in reasonable quantities through airport security to be able to feed your baby.
You can even bring the formula powder through airport security and then make the formula for your baby on board the plane and the flight attendants will get you some water to be able to make the baby formula to feed your baby.
The rules for liquids don't apply for the baby formula because your baby needs the formula or milk to feed them so your baby won't go hungry on the plane.