They would both best be characterized as a mixture, because neither is anything approaching homogenous. If you mean just the chicken broth part of the soup, that iself might be characterized as a suspension, since it's usually got all kinds of little particles floating around in it, bits of chicken and fat and whatnot. It's not clear, you'll note, and you often get a sediment if you let it sit for a while. A cloudy broth that doesn't settle might be characterized as a colloid -- tiny globs of fat in the water. And a perfectly clear broth might well be a solution, with proteins and salt and so forth simply dissolved in it.