Tom Brady’s kids aren’t impressed by his success. Before the ex-NFL star, 46, took the stage to be skewered by his friends and former teammates at The Greatest Roast of All Time: Tom Brady on Sunday, May 5, he revealed that his three children don’t think he’s the coolest dad on the block. “I’m just their dad, so everything I do is lame and, you know, there’s nothing I do that’s right,” he explained during a red carpet interview. “But it’s fun being a dad. I’ve got some great kids.” The former New England Patriots quarterback shares Vivian, 11, and Benjamin, 14, with his ex-wife, Gisele Bündche…