x86: fix build warnings in real mode code

This recent patch

commit c3965bd
Author: Paul Jackson <pj@sgi.com>
Date:   Wed May 14 08:15:34 2008 -0700

    x86 boot: proper use of ARRAY_SIZE instead of repeated E820MAX constant

caused these new warnings during a normal build:

In file included from linux-2.6/arch/x86/boot/memory.c:17:
linux-2.6/include/linux/log2.h: In function '__ilog2_u32':
linux-2.6/include/linux/log2.h:34: warning: implicit declaration of function 'fls'
linux-2.6/include/linux/log2.h: In function '__ilog2_u64':
linux-2.6/include/linux/log2.h:42: warning: implicit declaration of function 'fls64'
linux-2.6/include/linux/log2.h: In function '__roundup_pow_of_two ':
linux-2.6/include/linux/log2.h:63: warning: implicit declaration of function 'fls_long'

I tried to fix them in log2.h, but it's difficult because the real mode
environment is completely different from a normal kernel environment. Instead
define an own ARRAY_SIZE macro in boot.h, similar to the other private
macros there.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/boot/boot.h

@@ -30,6 +30,8 @@
 /* Useful macros */
 #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
 
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
+
 extern struct setup_header hdr;
 extern struct boot_params boot_params;
 

arch/x86/boot/memory.c

@@ -13,7 +13,6 @@
  */
 
 #include "boot.h"
-#include <linux/kernel.h>
 
 #define SMAP	0x534d4150	/* ASCII "SMAP" */