If $frameworkcode and $op are not defined, it generates an error log entry.

I confirmed that "|| q{}" was safe for $op, as there was only one place it was used.

It is also safe for $frameworkcode, because it is impossible to enter nothing as a frameworkcode in biblio_framework. I checked back to biblio_framework because of the loop that does the "eq $frameworkcode" which floods the error log. The hashes are ultimately built from a select statement.

This bug was discovered in 3.8.5, it applies to 3.6.x, 3.8.x, and master.

Test Plan
---------
1) Login to staff client
2) Acquisitions
3) Search for a vendor (should exist)
4) enter a new basket (or existing basket)
5) "From an external source"
6) check error log file. There will be several errors like:

[Sat Oct 06 20:09:37 2012] [error] [client 192.168.100.2] [Sat Oct  6 20:09:37 2012] z3950_search.pl: Use of uninitialized value $frameworkcode in string eq at /usr/share/koha/intranet/cgi-bin/acqui/z3950_search.pl line 100.

And one like:
[Sat Oct 06 20:09:37 2012] [error] [client 192.168.100.2] [Sat Oct  6 20:09:37 2012] z3950_search.pl: Use of uninitialized value $op in string ne at /usr/share/koha/intranet/cgi-bin/acqui/z3950_search.pl line 116.

7) apply patch
8) repeat steps, and those errors will not be generated.

Patch(es) to follow.