illumos gate

The loader support in bootadm was built keeping in mind the zfs based boot environments, each BE has two lines, title and bootfs line. To support other types of "boot environments", small update is needed. We would be specifically interested in supporting different type of entry for chainload support and different type of device:

tsoome@test:~$ bootadm list-menu
the location for the active menu is: /rpool/boot/menu.lst
Index  Default  Type    Device             Menu 
0      -        chain   disk1:             Disk1
1      -        chain   disk2:             Disk2
2      -        chain   disk3:             Disk3
3      -        bootfs  disk3s1a:          Disk3_ufs
4      -        bootfs  rpool/ROOT/oi-431  oi-431
5      *        bootfs  rpool/ROOT/oi-432  oi-432

So, we should have the entry type column for menu listing; and we need to take account that the menu.lst entry may not have the corresponding entry in zfs dataset list. Note that with this change, we only address the menu listing, not creation/change.