RAMFS_COPY_* are moved to platform.sh toplevel. The unneeded
linksys_preupgrade function is removed, and the nand_do_upgrade call is
moved to platform_do_upgrade.
Fixes: 30f61a34b4 "base-files: always use staged sysupgrade"
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
When running sysupgrade for the first time over the second partition
(that still had stock firmware) the rootfs wasn't flashed as there
wasn't enough space.
This happend because stock also uses UBI, but the volume name wasn't
recognised and wasn't deleted before flashing.
Signed-off-by: Adrian Panella <ianchi74@outlook.com>