Bug 25914: Fix incorrect variable name causing relative's checkouts column to be...

Bug 25914: Fix incorrect variable name causing relative's checkouts column to be empty in OPAC

In the OPAC, the title column in the relatives checkouts table is always empty.

Test Plan:
1) Enable viewing of relative's checkouts in OPAC
2) Check some items out to a patron
3) Log into the OPAC as a relative of that patron that should be able to
   view them
4) Note the title column is empty in the relative's checkouts tab
5) Apply this patch
6) Reload the page
7) Titles should appear in the title column!

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Alex Arnaud <alex.arnaud@biblibre.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>