Update: A correction was made to clarify that the name of Peter D. Sullivan’s late father is Harold W. Sullivan.Peter D. Sullivan, a 36-year veteran of Hinshaw & Culbertson LLP, was recently elected as the firm’s top lawyer.“I was pretty excited that a number of partners in the firm asked me to step up and take the position, and I agreed to do it,” Sullivan said.The firm announced the change on Friday. He is only the third chairman in the past 30 years.When Donald L. Mrozek, who served as …