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/drivers/scsi/Makefile b/drivers/scsi/Makefile
index 9e23699..6fc5f4a 100644
--- a/drivers/scsi/Makefile
+++ b/drivers/scsi/Makefile
@@ -1,9 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0+
 #
 # (C) Copyright 2000-2007
 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
-#
-# SPDX-License-Identifier:	GPL-2.0+
-#
 
 ifndef CONFIG_SPL_BUILD
 obj-$(CONFIG_DM_SCSI) += scsi-uclass.o
diff --git a/drivers/scsi/sandbox_scsi.c b/drivers/scsi/sandbox_scsi.c
index ac60ae0..39b969a 100644
--- a/drivers/scsi/sandbox_scsi.c
+++ b/drivers/scsi/sandbox_scsi.c
@@ -1,9 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0+
 /*
  * Copyright (C) 2015 Google, Inc
  * Written by Simon Glass <sjg@chromium.org>
  *
- * SPDX-License-Identifier:	GPL-2.0+
- *
  * This file contains dummy implementations of SCSI functions requried so
  * that CONFIG_SCSI can be enabled for sandbox.
  */
diff --git a/drivers/scsi/scsi-uclass.c b/drivers/scsi/scsi-uclass.c
index 31e8999..acf3b3d 100644
--- a/drivers/scsi/scsi-uclass.c
+++ b/drivers/scsi/scsi-uclass.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0+
 /*
  * Copyright (c) 2015 Google, Inc
  * Written by Simon Glass <sjg@chromium.org>
@@ -5,8 +6,6 @@
  * Written by Michal Simek
  *
  * Based on ahci-uclass.c
- *
- * SPDX-License-Identifier:	GPL-2.0+
  */
 
 #include <common.h>
diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c
index df99892..16246be 100644
--- a/drivers/scsi/scsi.c
+++ b/drivers/scsi/scsi.c
@@ -1,8 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0+
 /*
  * (C) Copyright 2001
  * Denis Peter, MPL AG Switzerland
- *
- * SPDX-License-Identifier:	GPL-2.0+
  */
 
 #include <common.h>