PHOTO: Mike Krzyzewski and Herman Bulls at Coach K's annual Duke leadership seminar. By TOM SHANAHAN DURHAM – Herman Bulls knew Mike Krzyzewski early on, long before Duke’s basketball Hall-of-Famer was Coach K, his iconic identity. He was an unknown Army coach with a silent K preceding his tongue-twisting surname. Similarly, Krzyzewski knew Bulls when he was merely a budding West Point cadet broadcasting Army basketball games on the campus radio station, WKDT. Bulls had yet to start…