Otherwise, non-string properties without a legacy counterpart are missed.
Also fix error propagation in object_property_print() itself.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>