mt76: dma: use kzalloc instead of devm_kzalloc for txwi

dma unmap is already needed for cleanup anyway, so we don't need the extra
tracking and can save a bit of memory here
Signed-off-by: Felix Fietkau <nbd@nbd.name>

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

@@ -16,7 +16,7 @@ mt76_alloc_txwi(struct mt76_dev *dev)
 	int size;
 
 	size = L1_CACHE_ALIGN(dev->drv->txwi_size + sizeof(*t));
-	txwi = devm_kzalloc(dev->dev, size, GFP_ATOMIC);
+	txwi = kzalloc(size, GFP_ATOMIC);
 	if (!txwi)
 		return NULL;
 
@@ -73,9 +73,11 @@ mt76_free_pending_txwi(struct mt76_dev *dev)
 	struct mt76_txwi_cache *t;
 
 	local_bh_disable();
-	while ((t = __mt76_get_txwi(dev)) != NULL)
+	while ((t = __mt76_get_txwi(dev)) != NULL) {
 		dma_unmap_single(dev->dev, t->dma_addr, dev->drv->txwi_size,
 				 DMA_TO_DEVICE);
+		kfree(mt76_get_txwi_ptr(dev, t));
+	}
 	local_bh_enable();
 }