Standardise header guards across codebase

All identifiers, regardless of use, that start with two underscores are
reserved. This means they can't be used in header guards.

The style that this project is now to use the full name of the file in
capital letters followed by 'H'. For example, for a file called
"uart_example.h", the header guard is UART_EXAMPLE_H.

The exceptions are files that are imported from other projects:

- CryptoCell driver
- dt-bindings folders
- zlib headers

Change-Id: I50561bf6c88b491ec440d0c8385c74650f3c106e
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
diff --git a/tools/fiptool/fiptool_platform.h b/tools/fiptool/fiptool_platform.h
index fd0a120..9bfa298 100644
--- a/tools/fiptool/fiptool_platform.h
+++ b/tools/fiptool/fiptool_platform.h
@@ -1,30 +1,31 @@
 /*
- * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
- *
+ */
+/*
  * Build platform specific handling.
  * This allows for builds on non-Posix platforms
  * e.g. Visual Studio on Windows
  */
 
-#ifndef __FIPTOOL_PLATFORM_H__
-#	define __FIPTOOL_PLATFORM_H__
+#ifndef FIPTOOL_PLATFORM_H
+#define FIPTOOL_PLATFORM_H
 
-#	ifndef _MSC_VER
+#ifndef _MSC_VER
 
-		/* Not Visual Studio, so include Posix Headers. */
-#		include <getopt.h>
-#		include <openssl/sha.h>
-#		include <unistd.h>
+/* Not Visual Studio, so include Posix Headers. */
+# include <getopt.h>
+# include <openssl/sha.h>
+# include <unistd.h>
 
-#		define  BLD_PLAT_STAT stat
+# define  BLD_PLAT_STAT stat
 
-#	else
+#else
 
-		/* Visual Studio. */
-#		include "win_posix.h"
+/* Visual Studio. */
+# include "win_posix.h"
 
-#	endif
+#endif
 
-#endif /* __FIPTOOL_PLATFORM_H__ */
+#endif /* FIPTOOL_PLATFORM_H */