amd-xgbe: fix potential memory leak in xgbe-debugfs

Added kfree() to avoid the memory leak when debugfs_create_dir() fails.
Signed-off-by: Geliang Tang <geliangtang@163.com>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/amd/xgbe/xgbe-debugfs.c

@@ -330,6 +330,7 @@ void xgbe_debugfs_init(struct xgbe_prv_data *pdata)
 	pdata->xgbe_debugfs = debugfs_create_dir(buf, NULL);
 	if (!pdata->xgbe_debugfs) {
 		netdev_err(pdata->netdev, "debugfs_create_dir failed\n");
+		kfree(buf);
 		return;
 	}