Comment 2 for bug 2003222

In curtin we could check if /sys/firmware/efi/efivars exists. If it does not exist update_nvram has to be False.

I wonder why the problem did not occur on the U-Boot based riscv64 platforms. There EFI variables can be read but not set. Maybe as we start with a system without boot options we simply do not try to delete or reorder boot options.