PSCI: Add missing function argument names

Fix MISRA C-2012 Rules 8.2 and 21.1.

Change-Id: I7f41fe76fe16399734d11847ab601ad8eb78df1a
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

include/lib/psci/psci_lib.h

 /*
- * 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 __PSCI_LIB_H__
-#define __PSCI_LIB_H__
+#ifndef PSCI_LIB_H
+#define PSCI_LIB_H
 
 #include <ep_info.h>
 
@@ -20,9 +20,9 @@
  ******************************************************************************/
 typedef struct spd_pm_ops {
 	void (*svc_on)(u_register_t target_cpu);
-	int32_t (*svc_off)(u_register_t __unused);
+	int32_t (*svc_off)(u_register_t __unused unused);
 	void (*svc_suspend)(u_register_t max_off_pwrlvl);
-	void (*svc_on_finish)(u_register_t __unused);
+	void (*svc_on_finish)(u_register_t __unused unused);
 	void (*svc_suspend_finish)(u_register_t max_off_pwrlvl);
 	int32_t (*svc_migrate)(u_register_t from_cpu, u_register_t to_cpu);
 	int32_t (*svc_migrate_info)(u_register_t *resident_cpu);
@@ -89,5 +89,4 @@ void psci_prepare_next_non_secure_ctx(
 			  entry_point_info_t *next_image_info);
 #endif /* __ASSEMBLY__ */
 
-#endif /* __PSCI_LIB_H */
-
+#endif /* PSCI_LIB_H */