mt76: mt76u: introduce mt76u_free_rx_queue utility routine

Introduce mt76u_free_rx_queue utility routine to free rx hw queue.
This is a preliminary patch to support new devices (e.g. mt7663u) that
rely on a hw queue for mcu messages
Co-developed-by: NSean Wang <sean.wang@mediatek.com>
Signed-off-by: NSean Wang <sean.wang@mediatek.com>
Signed-off-by: NLorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: NFelix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/usb.c

@@ -627,9 +627,9 @@ static int mt76u_alloc_rx(struct mt76_dev *dev)
 	return mt76u_submit_rx_buffers(dev, MT_RXQ_MAIN);
 }
 
-static void mt76u_free_rx(struct mt76_dev *dev)
+static void
+mt76u_free_rx_queue(struct mt76_dev *dev, struct mt76_queue *q)
 {
-	struct mt76_queue *q = &dev->q_rx[MT_RXQ_MAIN];
 	struct page *page;
 	int i;
 
@@ -644,6 +644,13 @@ static void mt76u_free_rx(struct mt76_dev *dev)
 	memset(&q->rx_page, 0, sizeof(q->rx_page));
 }
 
+static void mt76u_free_rx(struct mt76_dev *dev)
+{
+	struct mt76_queue *q = &dev->q_rx[MT_RXQ_MAIN];
+
+	mt76u_free_rx_queue(dev, q);
+}
+
 void mt76u_stop_rx(struct mt76_dev *dev)
 {
 	struct mt76_queue *q = &dev->q_rx[MT_RXQ_MAIN];