[Libvir] [PATCH] Allow virDomainDefine to overwrite existing inactive domains for xen 3.0.3 userspace installations

virDomainDefineXML should overwrite an existing inactive domain config if it finds one; it does this successfully for later (post 3.0.3) xen versions. However on xen 3.0.3 overwriting an existing config would fail with a name conflict. This patch allows the overwrite, removing the prior config from the config hashes. If someone more familiar than I with libvirt error handling and style could look at this and tell me if I've done something horribly wrong, I'd appreciate it. Signed-off-by: Hugh Brock <hbrock@redhat.com> -- Red Hat Virtualization Group http://redhat.com/virtualization Hugh Brock | virt-manager http://virt-manager.org hbrock@redhat.com | virtualization library http://libvirt.org