Instead of only displaying the property missing, also display
the object name. This help developer to quickly figure out the
mistake without opening a debugger.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Li Qiang <liq3ea@gmail.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200920155340.401482-1-f4bug@amsat.org>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>