If Fvb is a NULL, return EFI_UNSUPPORTED. If the remaining size is not enough, return EFI_OUT_OF_RESOURCES. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: cinnamon shia <cinnamon.shia@hpe.com> Signed-off-by: Ansen Huang <ansen.huang@hpe.com> Reviewed-by: Star Zeng <star.zeng@intel.com>