Can you cite that? Boko Haram is an Islamist movement, so I would expect them to recognize fellow Islamists anywhere of any race, and indeed Wikipedia notes they are allied with Islamic State in the Levant and Iraq. There are many Islamists who absolutely anyone would recognize as white, just look at some of the people from the Balkans or Chechnya who have gone to fight for ISIS.
There have been recent movements in Nigeria that specifically opposed whites in general, but they have generally been from an Afrocentrism perspective and often were just as mistrustful of Islam as Christianity, arguing for a return to indigenous African spirituality instead.