mdesc_get_prop_str
str = mdesc_get_prop_str(arc, "vcc-domain-name");
name = mdesc_get_prop_str(sc->sc_idx, "vds-block-device");
str = mdesc_get_prop_str(arc, "vldc-svc-name");
const char *mdesc_get_prop_str(int, const char *);
str = mdesc_get_prop_str(idx, "name");
str = mdesc_get_prop_str(arc, "name");