Legally? Nothing.

No. Benteke is on his own half of the field when the ball is played to him so he can’t be offside, and the last defender is beyond him anyways. Freeze the video at 0:07 or the replay at 0:27.

He’s not only behind the halfway line when the pass is made but there is also a defender and the goalie ahead of him.
In summary, you’re offside. And blind.