bridge_set_priority
if (bridge_set_priority(bif, val->v.integer) < 0)
bridge_set_priority(bif, ctx->scratch->int1);
if (bridge_set_priority(bif, val->v.integer) < 0)
bridge_set_priority(bif, ctx->scratch->int1);
int bridge_set_priority(struct bridge_if *bif, int32_t priority);