If you mean the iso folder it doesn't matter because most if not all uefi firmware boot from eltorito virtual fat32 boot sector, not from udf filesystem on DVD. If you mean redoing the efisys.bin bootsector to include both efi loaders it might work, problem is both efi loaders don't fit inside a standard 1.44 Mb disk image, I'm not sure if el torito supports a bigger disk image...