Bug 22620: OPAC description for CCODE in opac-reserve.tt

Bug 22620: OPAC description for CCODE in opac-reserve.tt

Bug 20450 added CCODE to opac-reserve.tt using AuthorisedValues TT plugin.

This patch changes the plugin call so that it requests OPAC description.

Test plan :
1) Define a CCODE with staff and OPAC descriptions
2) Apply this collection on an item
3) At OPAC, place an hold on this item
4) Verify the collection display correctly OPAC description and not staff description

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>