Move SIZE_FROM_LOG2_WORDS macro to utils.h

This patch moves the macro SIZE_FROM_LOG2_WORDS() defined in
`arch.h` to `utils.h` as it is utility macro.

Change-Id: Ia8171a226978f053a1ee4037f80142c0a4d21430

bl1/bl1_main.c

@@ -38,6 +38,7 @@
 #include <platform.h>
 #include <platform_def.h>
 #include <smcc_helpers.h>
+#include <utils.h>
 #include "bl1_private.h"
 #include <uuid.h>
 

include/lib/aarch64/arch.h

 /*
- * Copyright (c) 2013-2015, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2016, 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:
@@ -334,8 +334,6 @@
 #define CTR_IMINLINE_MASK	0xf
 
 #define MAX_CACHE_LINE_SIZE	0x800 /* 2KB */
-#define SIZE_FROM_LOG2_WORDS(n)	(4 << (n))
-
 
 /* Physical timer control register bit fields shifts and masks */
 #define CNTP_CTL_ENABLE_SHIFT   0

include/lib/utils.h

@@ -38,6 +38,8 @@
 #define IS_POWER_OF_TWO(x)			\
 	(((x) & ((x) - 1)) == 0)
 
+#define SIZE_FROM_LOG2_WORDS(n)		(4 << (n))
+
 /*
  * The round_up() macro rounds up a value to the given boundary in a
  * type-agnostic yet type-safe manner. The boundary must be a power of two.