Why bring the menu up in a confrontational way?
"We're having turkey, potatoes, muffins, salad, cranberry sauce, and veggies, and a pumpkin cake for dessert - and of course, we'd love it if FIL will bring his homemade bread, but we've got everything else taken care of!"
That way, you've got the menu described, you've established what addition is welcome (bread) and what are not (everything else) and you don't have to have a big fuss over it.
It's a lot better to treat things you think might produce a negative reaction like they're completely normal than to present them defensively.
It isn't even accurate to say that you're not making the traditional dishes, because you are - I've seen many variations on turkey preparation (deep fried, cajun-flavored deep fried, smoked, roasted, etc.) a dozen variations on potatoes (one extended family T-day potluck produced EIGHT different potato dishes that I saw!), numerous ways to make stuffing, all sorts of vegetables made all sorts of ways, all kinds of bread, and many assorted cakes and pies. Ham frequently shows up on my family's Thanksgiving table as well. Some years, my mother decides that she's bored with turkey and ham and gets a goose. There isn't just one tradition - there are many.