WIP: [v20.05] Make osk-sdl fast on the PinePhone!

This makes osk-sdl nice and fast on the PinePhone, see https://public.z3ntu.xyz/VID_20200907_223954.mp4

This also makes usb keyboard input less frustrating to use as that seems to be hindered by the rendering somehow

Also with this the initramfs-extra size increases from 6.6M to a whopping 31M which isn't optimal but shouldn't be a problem for the pinephone