playing the devil's advocate here, the name "mana" for the concept in question came much later than its incorporation into video games (as "MP"), which argues against the concept having been borrowed from the culture that had the word "mana". and at least after the fact, MP are an obvious solution for the problem of rate limiting spells - so it's plausible to argue that the inherent concept probably would have shown up in games independently of any particular tribal society using it in their formulation of magic or not.