Bug 20310: (follow-up) Add or remove orgcode in second try

Bug 20310: (follow-up) Add or remove orgcode in second try

We did remove an orgcode, but we could also do the other way
around.

Note: Hard to include in the unit test since it mocks the whole
search engine part.

Test plan:
[1] Run t/db_dependent/Koha/Biblio/host_record.t
[2] Test host 001 = number and child 773 = (org)number
[3] Test host 001 = (org)number and child 773 = number

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>