an MBR with a first partiton table entry that bears non-zero start address.
A second set of volume descriptors and directory tree+tables gets created
which can be used to mount the image at the partition start.
Not yet implemented for second set: ISO 9660:1999, MD5 checksums.
New API calls iso_image_add_boot_image() , iso_image_get_all_boot_imgs(),
el_torito_get_boot_platform_id(), el_torito_get_load_seg(),
el_torito_get_load_size(), el_torito_get_bootable()
New inner call make_isolinux_mbr() produces a bootable System Area
from an ISOLINUX mbr/isohdp[fp]x*.bin file and an ISOLINUX
El Torito bootable image (isolinux.bin).
With the specified isolinux option, a MBR is written to the system area, and this
allows the image to boot from either CD/DVD or USB sticks.
This is also supported on overwriteable media (note that system area is always
overwritten), but it should not work on multisession media.