Attic insulation: Giving unfaced insulation a face
Nope, you don't need it. A paper facer on batt insulation is a vapor retarder, not barrier, and you don't want a vapor barrier or need a vapor retarder. Install it and be happy.

Additionally, save the loose insulation (assuming it's not asbestos-laden vermiculite...) and pile it on top of the batts once you're finished. If the final result isn't 12 inches thick, get more loose insulation, preferably cellulose or mineral wool, and keep on piling it up until you have 15 inches or more up there. Every little bit helps.