x86: added 'ifndef _ASM_X86_IOMAP_H' to iomap.h

iomap.h misses the include guards.

[ Impact: cleanup ]
Signed-off-by: Remis Lima Baima <remis.developer@googlemail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
LKML-Reference: <200904301836.23885.arnd@arndb.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/include/asm/iomap.h

+#ifndef _ASM_X86_IOMAP_H
+#define _ASM_X86_IOMAP_H
+
 /*
  * Copyright © 2008 Ingo Molnar
  *
@@ -31,3 +34,5 @@ iomap_atomic_prot_pfn(unsigned long pfn, enum km_type type, pgprot_t prot);
 
 void
 iounmap_atomic(void *kvaddr, enum km_type type);
+
+#endif /* _ASM_X86_IOMAP_H */