lima & panfrost driver (mesa) has been pushed to beta.armbian.com, if you already use beta image or use beta armbian software repo, please just update. if not please add armbian beta software repo, and update.   newer version (19.3-develop) mesa will be installed.   you need to follow https://gitlab.freedesktop.org/lima/web#xorgconf to configure your Xserver.   then enjor your mali GPU.