DJ AM and Travis Barker will open the free concert scheduled for Sept. 19 in Five Points. But the headliner still has not been booked. DJ AM, whose real name is Adam Goldstein, is a former member of the rock band Crazy Town. AM, who will perform on Sunday’s MTV Video Music Awards, is known for mashing punk, rock and rap beats. Barker, the former drummer for pop-punk band Blink-182 and a current member of +44, is known for collaborations, including with DJ AM. Most recently, Barker played on “Dope Boys,” a song on The Game’s album “LAX.” ...