gpu: drm: stm: Adopt SPDX identifiers

Add SPDX identifiers to files under stm directory
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Acked-by: Vincent Abriou <vincent.abriou@st.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171206112947.9569-1-benjamin.gaignard@st.com

drivers/gpu/drm/stm/drv.c

+// SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (C) STMicroelectronics SA 2017
  *
@@ -5,8 +6,6 @@
  *          Yannick Fertre <yannick.fertre@st.com>
  *          Fabien Dessenne <fabien.dessenne@st.com>
  *          Mickael Reulier <mickael.reulier@st.com>
- *
- * License terms:  GNU General Public License (GPL), version 2
  */
 
 #include <linux/component.h>

drivers/gpu/drm/stm/dw_mipi_dsi-stm.c

+// SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (C) STMicroelectronics SA 2017
  *
  * Authors: Philippe Cornu <philippe.cornu@st.com>
  *          Yannick Fertre <yannick.fertre@st.com>
- *
- * License terms:  GNU General Public License (GPL), version 2
  */
 
 #include <linux/clk.h>

drivers/gpu/drm/stm/ltdc.c

+// SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (C) STMicroelectronics SA 2017
  *
@@ -5,8 +6,6 @@
  *          Yannick Fertre <yannick.fertre@st.com>
  *          Fabien Dessenne <fabien.dessenne@st.com>
  *          Mickael Reulier <mickael.reulier@st.com>
- *
- * License terms:  GNU General Public License (GPL), version 2
  */
 
 #include <linux/clk.h>

drivers/gpu/drm/stm/ltdc.h

+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Copyright (C) STMicroelectronics SA 2017
  *
@@ -5,8 +6,6 @@
  *          Yannick Fertre <yannick.fertre@st.com>
  *          Fabien Dessenne <fabien.dessenne@st.com>
  *          Mickael Reulier <mickael.reulier@st.com>
- *
- * License terms:  GNU General Public License (GPL), version 2
  */
 
 #ifndef _LTDC_H_