Calls to break up Yum! Brands Inc. seem to be getting louder today, after the company put out a disappointing earnings release as a result of a slower-than-expected recovery in China yesterday. Meantime, shares of Yum (NYSE: YUM), which owns Irvine-based Taco Bell Corp. as well as the KFC and Pizza Hut brands, dropped about 19 percent to $67.52 per share by early afternoon Wednesday. Yum missed expectations when it posted slightly higher third-quarter earnings yesterday afternoon, with net income…