[][Fix mtk eth probe fail issue]

[Description]
Fix mtk eth probe fail issue

[Release-log]
N/A

Change-Id: I44162bc3108ccb2b2938b12d41648ca255af36dc
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/5116733
diff --git a/target/linux/mediatek/files-5.4/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/target/linux/mediatek/files-5.4/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index ca88795..f67237e 100755
--- a/target/linux/mediatek/files-5.4/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/target/linux/mediatek/files-5.4/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -614,7 +614,7 @@
 	eth->mii_bus->priv = eth;
 	eth->mii_bus->parent = eth->dev;
 
-	if(snprintf(eth->mii_bus->id, MII_BUS_ID_SIZE, "%pOFn", mii_np)) {
+	if(snprintf(eth->mii_bus->id, MII_BUS_ID_SIZE, "%pOFn", mii_np) < 0) {
 		ret = -ENOMEM;
 		goto err_put_node;
 	}