Small fixes:

• [buildarmimg] use latest rootfs from github instead of OSDN
• [buildarmimg] generate and use PARTUUID's in fstab and bootscripts as part the image generation process
• [buildarmimg] only use https mirrors in generated images
• [buildarmimg] remove the keyrings generated during build process. Is now handled on first boot instead by manjaro-system package
• [buildarmimg] expand the -k flag to now also take URLs as repository to add

New device support:

• [buildarmimg] Add support for Odroid HC4 (ohc4)
• [buildarmimg] Add support for Pinebook Pro with BSP uboot (pbpro-bsp device)