The build system took the DTB_SIZE definition from Default and not from
production-dtb under some conditions. Move the size definitions to
Default now as it is only used in production-dtb anyway.
Thanks Mathias Kresin for helping me with this.
Fixes: c2f052acae ("at91: convert boards to generic build target")
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Hauke Mehrtens