Heat olive oil in a Dutch oven over medium-high. Add onion, celery, garlic, oregano, cumin, and chili powder; cook, stirring constantly, 5 minutes. Add tomatillos; cook, stirring constantly, 1 minute. Add Turkey Stock, hominy, and green chiles; bring to a boil. Stir in roast turkey; reduce heat to low, and simmer until heated through, about 20 minutes. Remove from heat, and stir in cilantro, lime juice, salt, and pepper. Serve immediately with toppings.