We already know that the iPhone 15 will likely have USB-C, an A17 chip, and a periscope camera, but here’s one we haven’t heard before: Apple might be replacing the power and volume buttons in the iPhone 15 Pro with a new solid-state design. According to Ming-Chi Kuo, “the volume button and power button of two high-end iPhone 15/2H23 new iPhone models may adopt a solid-state button design (similar to the home button design of iPhone 7/8/SE2 & 3) to replace the physical/mechanical button design.” To accomplish this, Kuo says, Apple will add a pair of Taptic Engine motors to either side of the p…