ATLANTA — OG Anunoby entered this postseason as one of the league’s most invaluable supporting players. He left the first round with the look of a leading man.  In a first-round matchup featuring multiple All-Stars on both sides, Anunoby emerged as the series’ standout player. In the Game 6 clincher, the 28-year-old elevated his game again, leading the Knicks with 29 points, seven rebounds, two assists and four steals while shooting 11-of-14 from the field (4-of-6 from 3) in 29 minutes of the 140-89 win at State Farm Arena . Anunoby — who had 26 points, four steals and seven rebounds while helping the Knicks set a playoff record by amassing a 47-point halftime lead — finished the series averaging 21.5 points, 8.7 rebounds and 1.8 steals while shooting over 61 percent from the field and better than 60 percent on 3-pointers (17 of 28).…