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/include/drivers/io/io_block.h b/include/drivers/io/io_block.h
index 4f3ab39..d6d32f9 100644
--- a/include/drivers/io/io_block.h
+++ b/include/drivers/io/io_block.h
@@ -4,8 +4,8 @@
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
-#ifndef __IO_BLOCK_H__
-#define __IO_BLOCK_H__
+#ifndef IO_BLOCK_H
+#define IO_BLOCK_H
 
 #include <io_storage.h>
 
@@ -25,4 +25,4 @@
 
 int register_io_dev_block(const struct io_dev_connector **dev_con);
 
-#endif /* __IO_BLOCK_H__ */
+#endif /* IO_BLOCK_H */
diff --git a/include/drivers/io/io_driver.h b/include/drivers/io/io_driver.h
index 8306407..587f137 100644
--- a/include/drivers/io/io_driver.h
+++ b/include/drivers/io/io_driver.h
@@ -4,8 +4,8 @@
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
-#ifndef __IO_DRIVER_H__
-#define __IO_DRIVER_H__
+#ifndef IO_DRIVER_H
+#define IO_DRIVER_H
 
 #include <io_storage.h>
 #include <stdint.h>
@@ -56,4 +56,4 @@
 /* Register an IO device */
 int io_register_device(const io_dev_info_t *dev_info);
 
-#endif  /* __IO_DRIVER_H__ */
+#endif /* IO_DRIVER_H */
diff --git a/include/drivers/io/io_dummy.h b/include/drivers/io/io_dummy.h
index abe77ec..edfc699 100644
--- a/include/drivers/io/io_dummy.h
+++ b/include/drivers/io/io_dummy.h
@@ -4,9 +4,9 @@
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
-#ifndef __IO_DUMMY_H__
-#define __IO_DUMMY_H__
+#ifndef IO_DUMMY_H
+#define IO_DUMMY_H
 
 int register_io_dev_dummy(const struct io_dev_connector **dev_con);
 
-#endif /* __IO_DUMMY_H__ */
+#endif /* IO_DUMMY_H */
diff --git a/include/drivers/io/io_fip.h b/include/drivers/io/io_fip.h
index 1131cc7..e0b5746 100644
--- a/include/drivers/io/io_fip.h
+++ b/include/drivers/io/io_fip.h
@@ -4,11 +4,11 @@
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
-#ifndef __IO_FIP_H__
-#define __IO_FIP_H__
+#ifndef IO_FIP_H
+#define IO_FIP_H
 
 struct io_dev_connector;
 
 int register_io_dev_fip(const struct io_dev_connector **dev_con);
 
-#endif /* __IO_FIP_H__ */
+#endif /* IO_FIP_H */
diff --git a/include/drivers/io/io_memmap.h b/include/drivers/io/io_memmap.h
index 70e4e55..87e3466 100644
--- a/include/drivers/io/io_memmap.h
+++ b/include/drivers/io/io_memmap.h
@@ -4,11 +4,11 @@
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
-#ifndef __IO_MEMMAP_H__
-#define __IO_MEMMAP_H__
+#ifndef IO_MEMMAP_H
+#define IO_MEMMAP_H
 
 struct io_dev_connector;
 
 int register_io_dev_memmap(const struct io_dev_connector **dev_con);
 
-#endif /* __IO_MEMMAP_H__ */
+#endif /* IO_MEMMAP_H */
diff --git a/include/drivers/io/io_semihosting.h b/include/drivers/io/io_semihosting.h
index a917f5a..e90ea5c 100644
--- a/include/drivers/io/io_semihosting.h
+++ b/include/drivers/io/io_semihosting.h
@@ -4,11 +4,11 @@
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
-#ifndef __IO_SH_H__
-#define __IO_SH_H__
+#ifndef IO_SEMIHOSTING_H
+#define IO_SEMIHOSTING_H
 
 struct io_dev_connector;
 
 int register_io_dev_sh(const struct io_dev_connector **dev_con);
 
-#endif /* __IO_SH_H__ */
+#endif /* IO_SEMIHOSTING_H */
diff --git a/include/drivers/io/io_storage.h b/include/drivers/io/io_storage.h
index 02308e3..c496d48 100644
--- a/include/drivers/io/io_storage.h
+++ b/include/drivers/io/io_storage.h
@@ -4,8 +4,8 @@
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
-#ifndef __IO_H__
-#define __IO_H__
+#ifndef IO_STORAGE_H
+#define IO_STORAGE_H
 
 #include <errno.h>
 #include <stdint.h>
@@ -101,4 +101,4 @@
 int io_close(uintptr_t handle);
 
 
-#endif /* __IO_H__ */
+#endif /* IO_STORAGE_H */