Fix a problem with open-ils.circ.holds.retrieve_all_from_title

Fix a problem with open-ils.circ.holds.retrieve_all_from_title

Anoop Atre spotted this bug that's triggered by selecting "View Holds"
from "Actions for Selected Record" in the catalog seen through the staff
client.

Said method would error out like this:

[2011-05-20 10:04:03] open-ils.circ [ERR
:31866:CStoreEditor.pm:109:13058333633194115] editor[0|1] request error
open-ils.cstore.direct.serial.issuance.id_list.atomic :
{"subscription":[]} : Exception:
OpenSRF::DomainObject::oilsMethodException 2011-05-20T10:04:03
OpenILS::Utils::CStoreEditor
/openils/lib/perl5/OpenILS/Utils/CStoreEditor.pm:412 <500>  Severe query
error -- see error log for more details

because when trying to gather issuance-type holds, it didn't properly test
whether there actually were any subscriptions and issuances related to
the bib record in question.

Signed-off-by: Lebbeous Fogle-Weekley <lebbeous@esilibrary.com>