Replace some memset call by zeromem

Replace all use of memset by zeromem when zeroing moderately-sized
structure by applying the following transformation:
memset(x, 0, sizeof(x)) => zeromem(x, sizeof(x))

As the Trusted Firmware is compiled with -ffreestanding, it forbids the
compiler from using __builtin_memset and forces it to generate calls to
the slow memset implementation. Zeromem is a near drop in replacement
for this use case, with a more efficient implementation on both AArch32
and AArch64.

Change-Id: Ia7f3a90e888b96d056881be09f0b4d65b41aa79e
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>
diff --git a/services/spd/tspd/tspd_common.c b/services/spd/tspd/tspd_common.c
index 3dcefea..70959d7 100644
--- a/services/spd/tspd/tspd_common.c
+++ b/services/spd/tspd/tspd_common.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -35,6 +35,7 @@
 #include <debug.h>
 #include <string.h>
 #include <tsp.h>
+#include <utils.h>
 #include "tspd_private.h"
 
 /*******************************************************************************
@@ -78,7 +79,7 @@
 	tsp_entry_point->spsr = SPSR_64(MODE_EL1,
 					MODE_SP_ELX,
 					DISABLE_ALL_EXCEPTIONS);
-	memset(&tsp_entry_point->args, 0, sizeof(tsp_entry_point->args));
+	zeromem(&tsp_entry_point->args, sizeof(tsp_entry_point->args));
 }
 
 /*******************************************************************************