[libvirt] [PATCH] avoid dumpXML segfault with recent Xen (3.4.0)

This is basically the patch by Sascha at https://bugzilla.redhat.com/show_bug.cgi?id=503254 with a couple of cleanups. I think it's low risk, and avoid a crash so I commited it. Basically ths SXPR syntax changed from (type vnc) to (vnc 1) for VNC vfb devices, and assuming something similar for sdl. The code checks first for type then backoff for vnc/sdl so I think this is backward compatible. 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/