Bug#573859: xqilla 2.2 dependency

[Daniël de Kok <me@danieldk.eu>]

For my build in an Ubuntu PPA, I added and built against xqilla 2.2 
packages. Porting dbxml to XQilla 2.3 does not seem to be a trivial task.

Unfortunately, it has been a while since Oracle released a new dbxml 
version.