Adjustment layers can be dragged between documents, but the associated mask will follow along. To avoid that, "park" the current mask on a temporary layer, replace the layer from the other document, and drag the mask back.
EDIT: oops, I assumed different documents. If the same document, see Bojan's reply. I'd just duplicate the layer and replace the mask by alt-dragging it back.
So basically I should delete the second one , then diblicate the first and put it in place where second one had been before. I am doing exactly this and find it a bit too tiresom . Hoped to put the adjuatment layer inside smart object but looks like it doesn't work that way. Or maybe some alt drug or something like with their masks .