Position racks in the upper and lower thirds of the oven; preheat to 425 degrees F. Line 2 baking sheets with foil. Mix 1 1/2 teaspoons chili powder, 1/2 teaspoon cumin, 3/4 teaspoon salt, the cinnamon and lime zest in a bowl. Rub the spice mixture all over the chicken, then transfer to one of the baking sheets; set aside until ready to roast.
Toss the hominy, squash, bell pepper, 2 tablespoons olive oil, the remaining 1/2 teaspoon each chili powder and cumin, and 1/4 teaspoon salt in a medium bowl. Spread on the other baking sheet.
Transfer the chicken to the upper oven rack and the hominy to the lower rack. Roast, stirring the hominy occasionally, until the hominy is lightly browned and the chicken is cooked through, about 25 minutes.
Transfer the hominy to a bowl and add the lime juice, the remaining 1 tablespoon olive oil, the scallions and cilantro. Season with salt and toss. Serve with the chicken and lime wedges.