PSCI: Fix types of definitions

Also change header guards to fix defects of MISRA C-2012 Rule 21.1.

Change-Id: Ied0d4b0e557ef6119ab669d106d2ac5d99620c57
Acked-by: Sumit Garg <sumit.garg@linaro.org>
Acked-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
diff --git a/plat/hisilicon/poplar/include/platform_def.h b/plat/hisilicon/poplar/include/platform_def.h
index 8e8f009..824ca34 100644
--- a/plat/hisilicon/poplar/include/platform_def.h
+++ b/plat/hisilicon/poplar/include/platform_def.h
@@ -1,11 +1,11 @@
 /*
- * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
-#ifndef __PLATFORM_DEF_H__
-#define __PLATFORM_DEF_H__
+#ifndef PLATFORM_DEF_H
+#define PLATFORM_DEF_H
 
 #include <arch.h>
 #include <common_def.h>
@@ -131,8 +131,8 @@
 
 /* Power states */
 #define PLAT_MAX_PWR_LVL		(MPIDR_AFFLVL1)
-#define PLAT_MAX_OFF_STATE		2
-#define PLAT_MAX_RET_STATE		1
+#define PLAT_MAX_OFF_STATE		U(2)
+#define PLAT_MAX_RET_STATE		U(1)
 
 /* Interrupt controller */
 #define PLAT_ARM_GICD_BASE	GICD_BASE
@@ -168,4 +168,4 @@
 
 #define PLAT_ARM_G0_IRQ_PROPS(grp)
 
-#endif /* __PLATFORM_DEF_H__ */
+#endif /* PLATFORM_DEF_H */