[PATCH] net: airoha: Clean up RX queues in airoha_dev_stop

[Wayen Yan <win847@gmail.com>]

When the last port is stopped, airoha_dev_stop() clears TX queues
but neglects to clean up RX queues. This can lead to:
- RX ring buffer descriptors remaining valid after device close
- Potential DMA synchronization issues on device reopen
- Risk of use-after-free if pages are freed while DMA is still active

Add cleanup loop for RX queues to mirror the TX queue cleanup,
ensuring symmetric resource management.

Fixes: 20bf7d07c956 ("net: airoha: add QDMA support for Airoha EN7581 Ethernet")
Signed-off-by: Wayen Yan <win847@gmail.com>
---
 drivers/net/ethernet/airoha/airoha_eth.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/net/ethernet/airoha/airoha_eth.c b/drivers/net/ethernet/airoha/airoha_eth.c
index 31cdb11cd7..9ca5bbf64d 100644
--- a/drivers/net/ethernet/airoha/airoha_eth.c
+++ b/drivers/net/ethernet/airoha/airoha_eth.c
@@ -1771,6 +1771,13 @@ static int airoha_dev_stop(struct net_device *dev)
 
 			airoha_qdma_cleanup_tx_queue(&qdma->q_tx[i]);
 		}
+
+		for (i = 0; i < ARRAY_SIZE(qdma->q_rx); i++) {
+			if (!qdma->q_rx[i].ndesc)
+				continue;
+
+			airoha_qdma_cleanup_rx_queue(&qdma->q_rx[i]);
+		}
 	}
 
 	return 0;
-- 
2.51.0