nvme-builtin: sort command list as alphabetical order

[ikegami-t]

This is to find easily the sub-commands name from the help list.

[igaw]

@MatiasBjorling updated the order of the zns commands so that most used come first. I don't know if we should order them or not. I see value in both orders.

We could also make sections if this would help, like the main commands like list, id-ctrl etc. and the plumbing commands go into their own section. And both could be alphabetically sorted.

[ikegami-t]

Understood so I will do try to consider more if any option or etc,. to sort the order can be added or not. Thank you.

[MatiasBjorling]

Thank you. If possible, I like to maintain a kind of "highlight" of the most used commands, making it easier to guide the user towards the commands that they're most likely to need.

[ikegami-t]

Thank you for your advice. I will do consider later.

[ikegami-t]

@igaw Changed the commit to filter the help command list instead of the sort changes.

[igaw]

Thanks!