Lil Nas X is back in action with a spirited return to social media. The Grammy Award-winning hip-hop superstar came back on Twitter Wednesday after taking a three-month hiatus from all social media, which had caused fans to worry about his unexpected disappearance. “why are people surprised i’ve been away for so long?” he wrote. “have y’all really never heard of maternity leave?” The “maternity leave” references the marketing campaign for the release of his debut album, “Montero” last fall, where the pop culture provocateur talked about it being a “baby” he was giving birth to. To take it one …