Both KM & digital learning share common digital infrastructure. They also share the common aim of creating & acquiring knowledge. In a book chapter in 2005 I outlined some of the commonalities: https://www.researchgate.net/publication/233414460_From_e-learning_to_e-knowledge
Things have certainly moved on since then so I'm now looking for recent research into this topic or re-conceptualisations of these two domains of activity.
Chapter From e-Learning to e-Knowledge