Export-image: disable metadata_csum for compatibility with older SD card copiers
Export-image: disable metadata_csum for compatibility with older SD card copiers

timcoote/Pumpkin-gen,cfstras/pi-gen,jacen92/pi-gen,rkubes/pi-gen,KingBrewer/pi-gen,drothmaler/pi-gen,timcoote/Pumpkin-gen,WLANThermo/pi-gen,RPi-Distro/pi-gen,brindosch/pi-gen,BlokasLabs/modep,DigitaleGesellschaft/pi-gen,timcoote/Pumpkin-gen,8devices/pi-gen,BlokasLabs/modep