Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/net/ethernet/micrel/ks8842.c b/drivers/net/ethernet/micrel/ks8842.c
index e3d7c74..da329ca 100644
--- a/drivers/net/ethernet/micrel/ks8842.c
+++ b/drivers/net/ethernet/micrel/ks8842.c
@@ -1,19 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * ks8842.c timberdale KS8842 ethernet driver
  * Copyright (c) 2009 Intel Corporation
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
 /* Supports:
@@ -592,9 +580,7 @@
 		dma_unmap_single(adapter->dev, sg_dma_address(sg),
 			DMA_BUFFER_SIZE, DMA_FROM_DEVICE);
 	sg_dma_address(sg) = 0;
-	if (ctl->skb)
-		dev_kfree_skb(ctl->skb);
-
+	dev_kfree_skb(ctl->skb);
 	ctl->skb = NULL;
 
 	printk(KERN_ERR DRV_NAME": Failed to start RX DMA: %d\n", err);