Bug 21260: Remove item details from reallynotforloan block

Bug 21260: Remove item details from reallynotforloan block

No need to display itemcallnumbers and branch info for items that
are ('really') not available.
We only show a status and a count for the reallynotforloan ('ordered')
categories (not per branch). This simplifies the code too.
We use the preceding-sibling axis to loop over the unique substatuses.

Test plan:
[1] Pick a biblio with an available item A, an item B with notforloan 1,
    an item C with notforloan 2 and two damaged items.
    Include it in a OPAC search. You should see:
        Available: A. Reference: B, C. Not-available: Damaged(2).
[2] Edit item C (notforloan 2). Change to notforloan -1.
    Search again. You should see:
        Available: A. Reference: B. Not-available: On order(1), Damaged(2).

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: ava li <rubyli208@gmail.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>