"But flesh with the life thereof, which is the blood thereof, shall ye not eat."
It's neither. The verse before it, that every living thing which moves shall be meat for you, clearly eliminates a prohibition on meat.
But life was associated with the blood of animals in the sacrifice. It was the blood of the lamb on the door that saved the Israelites during the passover in Egypt. It was the blood offering that was the sin offering. It's believed that's why cain's offering was rejected, is because it wasn't a blood offering. The whole sacrifice system was to foreshadow Jesus.
I don't know that the Israelites had a prohibition on canibalism, or needed one. They were to bury their dead. You couldn't kill a man, and dead things were unclean, so it was pretty much excluded.