WASHINGTON (Reuters) – U.S. President Joe Biden named former federal prosecutor and Chicago lawyer Ed Siskel as his top White House lawyer on Tuesday, saying the former White House deputy counsel would start his new post next month. Siskel served in the White House Counsel’s office for nearly four years when Biden was vice president under former President Barack Obama, including as deputy counsel, the White House said in a statement. “For nearly four years in the White House when I was vice president, he helped the Counsel’s Office navigate complex challenges and advance the president’s agenda…