Bug 17250 - Koha::AuthorisedValues - Remove GetAuthValCode

Bug 17250 - Koha::AuthorisedValues - Remove GetAuthValCode

The subroutine C4::Koha::GetAuthValCode returned the authorised value
category for a given kohafield.
This can be acchieve easily using a new Koha::AuthorisedValues->search_by_koha_field
method which will mimic search_by_marc_field.

Test plan:
Confirm that the description is correctly displayed on the following
pages:
- detail and moredetail of a bibliographic page (itemlost, damaged, materials)
- Set AcqCreateItem=ordering and receiving items.
The description for notforloan, restricted, location, ccode, etc.
field should be displayed.
- Items search form
- On the checkout list from the circulation.pl and returns.pl
pages, the description for "materials" should be displayed

Note that GetKohaAuthorisedValuesMapping is going to be removed on bug
17251.

Followed test plan, works as expected.
Signed-off-by: Marc Véron <veron@veron.ch>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>