“The Smashing Machine” is getting early Oscar buzz for Dwayne “The Rock” Johnson. At first, fans were shocked by the 53-year-old actor’s slimmed-down physique. But now, from “Fallon” to “GMA,” all anyone wants to talk about is the 15-minute standing ovation the biopic received at the Venice Film Festival. Meanwhile on A24’s TikTok page, fans…