x86: commonize smp.h

this is the first step of integrating smp.h between x86_64
and i386
Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

include/asm-x86/smp.h

+#ifndef _ASM_X86_SMP_H_
+#define _ASM_X86_SMP_H_
+#ifndef __ASSEMBLY__
+
 #ifdef CONFIG_X86_32
 # include "smp_32.h"
 #else
 # include "smp_64.h"
 #endif
+
+#endif /* __ASSEMBLY__ */
+#endif