virsh-completer: use VIR_AUTOPTR for xml* variables
virsh-completer: use VIR_AUTOPTR for xml* variables

Signed-off-by: Ján Tomko <4cab11cfb98d3c937327354a78eb07dbb6ee2bc6@redhat.com>

eskultety/libvirt,libvirt/libvirt,eskultety/libvirt,fabianfreyer/libvirt,jardasgit/libvirt,olafhering/libvirt,olafhering/libvirt,fabianfreyer/libvirt,fabianfreyer/libvirt,eskultety/libvirt,libvirt/libvirt,jardasgit/libvirt,jfehlig/libvirt,jardasgit/libvirt,olafhering/libvirt,eskultety/libvirt,libvirt/libvirt,zippy2/libvirt,zippy2/libvirt,olafhering/libvirt,zippy2/libvirt,jardasgit/libvirt,andreabolognani/libvirt,crobinso/libvirt,zippy2/libvirt,jardasgit/libvirt,jfehlig/libvirt,nertpinx/libvirt,fabianfreyer/libvirt,nertpinx/libvirt,eskultety/libvirt,jfehlig/libvirt,crobinso/libvirt,nertpinx/libvirt,nertpinx/libvirt,andreabolognani/libvirt,crobinso/libvirt,andreabolognani/libvirt,libvirt/libvirt,jfehlig/libvirt,andreabolognani/libvirt,nertpinx/libvirt,andreabolognani/libvirt,fabianfreyer/libvirt,crobinso/libvirt