Bug 20620: Remove warnings in moredetail.pl

Bug 20620: Remove warnings in moredetail.pl

Since 19995 warnings are displayed in moredetail.pl, we should get rid
of them.

Test plan:
Hit moredetail.pl with different biblionumbers and confirm you do no
longer see warnings in logs.

Make sure values for rentalcharge, item type, ccode and replacementprice
are displayed correctly.

Signed-off-by: Bouzid Fergani <bouzid.fergani@inlibro.com>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>