x86: consolidate header guards

This patch is the result of an automatic script that consolidates the
format of all the headers in include/asm-x86/.

The format:

1. No leading underscore. Names with leading underscores are reserved.
2. Pathname components are separated by two underscores. So we can
   distinguish between mm_types.h and mm/types.h.
3. Everything except letters and numbers are turned into single
   underscores.

Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
diff --git a/include/asm-x86/fixmap_32.h b/include/asm-x86/fixmap_32.h
index f1ac2b2..784e3e7 100644
--- a/include/asm-x86/fixmap_32.h
+++ b/include/asm-x86/fixmap_32.h
@@ -10,8 +10,8 @@
  * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
  */
 
-#ifndef _ASM_FIXMAP_32_H
-#define _ASM_FIXMAP_32_H
+#ifndef ASM_X86__FIXMAP_32_H
+#define ASM_X86__FIXMAP_32_H
 
 
 /* used by vmalloc.c, vsyscall.lds.S.
@@ -120,4 +120,4 @@
 #define FIXADDR_BOOT_START	(FIXADDR_TOP - __FIXADDR_BOOT_SIZE)
 
 #endif /* !__ASSEMBLY__ */
-#endif
+#endif /* ASM_X86__FIXMAP_32_H */