mt76: change the return type of mt76_dma_attach()

There is no need to retun 0 in mt76_dma_attach(), so switch it to void.
Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

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

@@ -553,10 +553,9 @@ static const struct mt76_queue_ops mt76_dma_ops = {
 	.kick = mt76_dma_kick_queue,
 };
 
-int mt76_dma_attach(struct mt76_dev *dev)
+void mt76_dma_attach(struct mt76_dev *dev)
 {
 	dev->queue_ops = &mt76_dma_ops;
-	return 0;
 }
 EXPORT_SYMBOL_GPL(mt76_dma_attach);
 

drivers/net/wireless/mediatek/mt76/dma.h

@@ -54,7 +54,7 @@ enum mt76_mcu_evt_type {
 	EVT_EVENT_DFS_DETECT_RSP,
 };
 
-int mt76_dma_attach(struct mt76_dev *dev);
+void mt76_dma_attach(struct mt76_dev *dev);
 void mt76_dma_cleanup(struct mt76_dev *dev);
 
 #endif