net: sched: using TCQ_MIN_PRIO_BANDS in prio_tune()

Using TCQ_MIN_PRIO_BANDS instead of magic number in prio_tune().
Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Link: https://lore.kernel.org/r/20220826041035.80129-1-shaozhengchao@huawei.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

net/sched/sch_prio.c

@@ -185,7 +185,7 @@ static int prio_tune(struct Qdisc *sch, struct nlattr *opt,
 		return -EINVAL;
 	qopt = nla_data(opt);
 
-	if (qopt->bands > TCQ_PRIO_BANDS || qopt->bands < 2)
+	if (qopt->bands > TCQ_PRIO_BANDS || qopt->bands < TCQ_MIN_PRIO_BANDS)
 		return -EINVAL;
 
 	for (i = 0; i <= TC_PRIO_MAX; i++) {