The example return type has the wrong member name. Fix it.

Problem was noticed when using the example as a test case for Go
bindings.

Signed-off-by: Victor Toso <victortoso@redhat.com>
Message-Id: <20220901085840.22520-10-victortoso@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>