sch_htb: fix doc warning in htb_remove_class_from_row()

Add description for parameters of htb_remove_class_from_row()
to fix gcc W=1 warnings:

net/sched/sch_htb.c:380: warning: Function parameter or member 'q' not described in 'htb_remove_class_from_row'
net/sched/sch_htb.c:380: warning: Function parameter or member 'cl' not described in 'htb_remove_class_from_row'
net/sched/sch_htb.c:380: warning: Function parameter or member 'mask' not described in 'htb_remove_class_from_row'
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/sched/sch_htb.c

@@ -381,6 +381,9 @@ static void htb_safe_rb_erase(struct rb_node *rb, struct rb_root *root)
 
 /**
  * htb_remove_class_from_row - removes class from its row
+ * @q: the priority event queue
+ * @cl: the class to add
+ * @mask: the given priorities in class in bitmap
  *
  * The class is removed from row at priorities marked in mask.
  * It does nothing if mask == 0.