media: platform: sti: Adopt SPDX identifier

Add SPDX identifiers to files under sti directory

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Reviewed-by: Fabien Dessenne <fabien.dessenne@st.com>
Acked-by: Philippe Ombredanne <pombredanne@nexb.com>
Acked-by: Hugues Fruchet <hugues.fruchet@st.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/platform/sti/cec/stih-cec.c

@@ -1,11 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * STIH4xx CEC driver
  * Copyright (C) STMicroelectronics SA 2016
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
  */
 #include <linux/clk.h>
 #include <linux/interrupt.h>