doc: Make examples a complete program
doc: Make examples a complete program

Add `package main` and declare a `main()` function.

Reviewed-by: Daniel P. Berrangé <bb938cf255e055ff3507f2627d214e8e62118fcf@redhat.com>
Signed-off-by: Philipp Hahn <8cb7a2c205789112a9f61bc3102305826b6a8db1@univention.de>

libvirt/libvirt-go-xml