OXT-1372: installer: Amend disk/partition for efibootmgr

[eric-ch]

Add two functions to the common script library to parse devnodes disk
and partition and use them with efibootmgr when writting efi boot
entries for a new OpenXT installation.

[jean-edouard]

This is definitely an improvement over the existing code, so I wouldn't mind merging it.
However... :p
You're only handling disks up to /dev/sdz, whereas Linux (reliably) handles up to /dev/sdzzz. That's definitely an edge case though.
Also, and this is even more picky, I think the /dev/sd* case could be generalized to /dev/*, since that's the most common scheme (letter for the disk followed by partition number), just in case we ever have to deal with stuff like nested virt or embedded drives.

Anyway, just a couple thoughts, feel free to ignore this :)

[eric-ch]

Anyway, just a couple thoughts, feel free to ignore this :)

Why would I!? ;) And it is not hard to fix really.

Also, and this is even more picky, I think the /dev/sd* case could be generalized to /dev/*, since that's the most common scheme (letter for the disk followed by partition number), just in case we ever have to deal with stuff like nested virt or embedded drives.

That part I do not understand... Could you elaborate?

EDIT:
Hang on... Linux admin-guide defines SCSI disks ranging from /dev/sda to /dev/sdiv with 16 partitions each. /dev/sdzzz should not be possible?
You still have a point though ;). In theory, the naming can go on and on... (SCSI disk name)

[eric-ch]

V2:

• Handle SCSI disk devnodes beyond /dev/sdz;
• Handle partitions on SCSI disk devnodes beyond 9.

[eric-ch]

V3:

• get_devnodes_partition should echo the partition number or nothing (do not match /dev/nvmeXnX).

[jean-edouard]

LGTM, merging soon.