SPDX: Convert all of our single license tags to Linux Kernel style

When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/arch/arm/cpu/armv7m/Makefile b/arch/arm/cpu/armv7m/Makefile
index 257fc7f..6c78d29 100644
--- a/arch/arm/cpu/armv7m/Makefile
+++ b/arch/arm/cpu/armv7m/Makefile
@@ -1,9 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0+
 #
 # (C) Copyright 2000-2006
 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
-#
-# SPDX-License-Identifier:	GPL-2.0+
-#
 
 extra-y := start.o
 obj-y += cpu.o cache.o mpu.o
diff --git a/arch/arm/cpu/armv7m/cache.c b/arch/arm/cpu/armv7m/cache.c
index a46d4b5..815e623 100644
--- a/arch/arm/cpu/armv7m/cache.c
+++ b/arch/arm/cpu/armv7m/cache.c
@@ -1,8 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0+
 /*
  * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
  * Author(s): Vikas Manocha, <vikas.manocha@st.com> for STMicroelectronics.
- *
- * SPDX-License-Identifier:	GPL-2.0+
  */
 
 #include <common.h>
diff --git a/arch/arm/cpu/armv7m/config.mk b/arch/arm/cpu/armv7m/config.mk
index db4660e..4e46df5 100644
--- a/arch/arm/cpu/armv7m/config.mk
+++ b/arch/arm/cpu/armv7m/config.mk
@@ -1,8 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0+
 #
 # (C) Copyright 2015
 # Kamil Lulko, <kamil.lulko@gmail.com>
-#
-# SPDX-License-Identifier:	GPL-2.0+
-#
 
 PLATFORM_CPPFLAGS += -march=armv7-m -mthumb -mno-unaligned-access
diff --git a/arch/arm/cpu/armv7m/cpu.c b/arch/arm/cpu/armv7m/cpu.c
index 2959775..55ea078 100644
--- a/arch/arm/cpu/armv7m/cpu.c
+++ b/arch/arm/cpu/armv7m/cpu.c
@@ -1,11 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0+
 /*
  * (C) Copyright 2010,2011
  * Vladimir Khusainov, Emcraft Systems, vlad@emcraft.com
  *
  * (C) Copyright 2015
  * Kamil Lulko, <kamil.lulko@gmail.com>
- *
- * SPDX-License-Identifier:	GPL-2.0+
  */
 
 #include <common.h>
diff --git a/arch/arm/cpu/armv7m/mpu.c b/arch/arm/cpu/armv7m/mpu.c
index e4d090e..d89d9f2 100644
--- a/arch/arm/cpu/armv7m/mpu.c
+++ b/arch/arm/cpu/armv7m/mpu.c
@@ -1,8 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0+
 /*
  * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
  * Author(s): Vikas Manocha, <vikas.manocha@st.com> for STMicroelectronics.
- *
- * SPDX-License-Identifier:	GPL-2.0+
  */
 
 #include <linux/bitops.h>
diff --git a/arch/arm/cpu/armv7m/start.S b/arch/arm/cpu/armv7m/start.S
index 890c773..0c07f21 100644
--- a/arch/arm/cpu/armv7m/start.S
+++ b/arch/arm/cpu/armv7m/start.S
@@ -1,8 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
 /*
  * (C) Copyright 2015
  * Kamil Lulko, <kamil.lulko@gmail.com>
- *
- * SPDX-License-Identifier:	GPL-2.0+
  */
 
 #include <asm/assembler.h>
diff --git a/arch/arm/cpu/armv7m/systick-timer.c b/arch/arm/cpu/armv7m/systick-timer.c
index 23244c3..d04f67a 100644
--- a/arch/arm/cpu/armv7m/systick-timer.c
+++ b/arch/arm/cpu/armv7m/systick-timer.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0+
 /*
  * ARM Cortex M3/M4/M7 SysTick timer driver
  * (C) Copyright 2017 Renesas Electronics Europe Ltd
@@ -9,8 +10,6 @@
  * Copyright 2015 ATS Advanced Telematics Systems GmbH
  * Copyright 2015 Konsulko Group, Matt Porter <mporter@konsulko.com>
  *
- * SPDX-License-Identifier:     GPL-2.0+
- *
  * The SysTick timer is a 24-bit count down timer. The clock can be either the
  * CPU clock or a reference clock. Since the timer will wrap around very quickly
  * when using the CPU clock, and we do not handle the timer interrupts, it is