NAJAF, July 7 (Reuters) - The coffin of Iran’s slain Supreme Leader Ayatollah Ali Khamenei arrived in Iraq’s holy city of Najaf on Tuesday, where Iraqi Prime Minister Ali al-Zaidi and senior Iraqi officials received it ahead of funeral ceremonies and a mass public procession, Iraqi state TV reported. The official reception at Najaf International Airport was attended by Iraqi political leaders and Shi’ite religious figures, before the coffin is carried through the city in public mourning events e