Add RTL8152 driver -- building kernel modules for Seeed OpenWrt distribution

@kees I’m also trying to add a Realtek 8152 chipset usb adapter. What I have found so far is GitHub - Seeed-Studio/seeed-linux-openwrt which are the build tools that seeed uses to create the images. No luck in how to use the build tools as it is a multi-step process that isn’t documented.