HOUSTON — Soon after he opened his office serving immigrants fighting to stay in the United States, Raed Gonzalez became a lawyer who goes after other lawyers.A person with a winnable case can be thrown into deportation by a missed deadline or a botched court filing, and attorneys quietly known by others to do bad legal work can practice for years without being stopped. So Gonzalez began helping immigrants file complaints against lawyers with their state licensing organizations. By his count, his firm has filed 90 complaints against lawyers in the last five years.