Bug 32712: Fix OPAC breakage when OPACShowCheckoutName enabled

Bug 32712: Fix OPAC breakage when OPACShowCheckoutName enabled

Bug 31313 removed GetItemsInfo and proper Koha::Object-based objects are
passed now. But some automatic search & replace kept patron-related
attributes incorrectly linked to Koha::Item.

This patch makes the item-status.inc file reuse the checkout object and
get the linked patron to gather the required information. Some
simplification is done on hte same patch... should be trivial.

To test:
1. Have OpacShowCheckoutName enabled
2. Pick a biblio with items (all of them not checkecd-out)
3. Open the OPAC detail view for the biblio
=> SUCCESS: You see the biblio and the items
4. Check one of the items out
5. Refresh the OPAC page
=> FAIL: The page explodes!
6. Apply this patch
7. Refresh the OPAC page
=> SUCCESS: You see the biblio and the items, the patron info is
correctly displayed.
8. Sign off :-D

Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>