By David Beasley ATLANTA (Reuters) - Chris "Mac Daddy" Kelly of the 1990s teen rap duo Kris Kross died in May from a drug overdose according to toxicology reports, authorities said on Tuesday. Mary Beth Hauptle, an investigator with the Fulton County Medical Examiner's office in Atlanta, released the test results to Reuters but declined to identify the drugs used. A friend of Kelly's told police that Kelly, 34, was using a mixture of heroin and cocaine on the evening before he was found unconscious in his Atlanta home on May 1, according to a police report. ...