[libvirt] [PATCH] PCI passthrough docs, tests and minor change

The following add the documentation for the PCI passthrough, extends the RNG and add an extra test for the QEmu parsing to args and serialization back to XML. I also noticed that we parse (and save) and extra PCI domain argument, but it's not actually used when calling qemu, so I assume it's a missing feature for QEmu and just decided to patch the code to not save the extra value when not defined (i.e. 0). Whether it should just be removed at this point is IMHO a separate decision, which is why I took the way with minimal changes. Note that the domain attribute is not documented nor part or the RNG either at this point. Daniel -- Daniel Veillard | libxml Gnome XML XSLT toolkit http://xmlsoft.org/ daniel(a)veillard.com | Rpmfind RPM search engine http://rpmfind.net/ http://veillard.com/ | virtualization library http://libvirt.org/