Former Department of Defense official Kash Patel is being considered for several national security posts — including CIA director, a key GOP source told The Post on Monday. Patel, 44, previously served as a National Security Council official, senior adviser to the acting director of national intelligence and chief of staff to the secretary of defense. While President-elect Donald Trump has not officially arrived a decision about Patel’s final move, there has been “conversations” between the transition team and the former Trump official — with the majority of the discussions in Trump World being focused on the CIA, according to...