Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/video/fbdev/tcx.c b/drivers/video/fbdev/tcx.c
index c98d8a5..7897f86 100644
--- a/drivers/video/fbdev/tcx.c
+++ b/drivers/video/fbdev/tcx.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /* tcx.c: TCX frame buffer driver
  *
  * Copyright (C) 2003, 2006 David S. Miller (davem@davemloft.net)