Summit Entertainment has started laying the groundwork for a “Red” sequel, returning to the scripting team of Jon and Erich Hoeber.A studio spokesman confirmed the attachment Monday while noting that Summit hasn’t yet greenlit a second installment of “Red,” which grossed $90 million domestically. Bruce Willis, Morgan Freeman, John Malkovich and Helen Mirren starred as former CIA agents who are classified as “Red” — retired, extremely dangerous. The Hoeber siblings adapted Warren Ellis’ comicbook for DC. They’re also the screenwriters on Universal’s tentpole “Battleship,” directed by Peter Berg. The Hoebers are repped by Verve and Cheng Caplan Co.