docs: fix iscsi-direct XML example
docs: fix iscsi-direct XML example

The <initiator> element is part of <source> element.

Reviewed-by: Ján Tomko <4cab11cfb98d3c937327354a78eb07dbb6ee2bc6@redhat.com>
Signed-off-by: Pavel Hrdina <d4772d05997b8abf035041e3b4f4996380ea7e7a@redhat.com>

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