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/marvell/cache_llc.h b/include/drivers/marvell/cache_llc.h
index 9e41793..1aa4c88 100644
--- a/include/drivers/marvell/cache_llc.h
+++ b/include/drivers/marvell/cache_llc.h
@@ -9,8 +9,8 @@
  * for Marvell SoCs in AP806, AP807, and AP810
  */
 
-#ifndef _CACHE_LLC_H_
-#define _CACHE_LLC_H_
+#ifndef CACHE_LLC_H
+#define CACHE_LLC_H
 
 #define LLC_CTRL(ap)			(MVEBU_LLC_BASE(ap) + 0x100)
 #define LLC_SYNC(ap)			(MVEBU_LLC_BASE(ap) + 0x700)
@@ -38,5 +38,4 @@
 void llc_runtime_enable(int ap_index);
 #endif
 
-#endif /* _CACHE_LLC_H_ */
-
+#endif /* CACHE_LLC_H */