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/xen/interface_32.h b/include/asm-x86/xen/interface_32.h
index d8ac41d..08167e1 100644
--- a/include/asm-x86/xen/interface_32.h
+++ b/include/asm-x86/xen/interface_32.h
@@ -6,8 +6,8 @@
  * Copyright (c) 2004, K A Fraser
  */
 
-#ifndef __ASM_X86_XEN_INTERFACE_32_H
-#define __ASM_X86_XEN_INTERFACE_32_H
+#ifndef ASM_X86__XEN__INTERFACE_32_H
+#define ASM_X86__XEN__INTERFACE_32_H
 
 
 /*
@@ -94,4 +94,4 @@
 #define xen_pfn_to_cr3(pfn) (((unsigned)(pfn) << 12) | ((unsigned)(pfn) >> 20))
 #define xen_cr3_to_pfn(cr3) (((unsigned)(cr3) >> 12) | ((unsigned)(cr3) << 20))
 
-#endif	/* __ASM_X86_XEN_INTERFACE_32_H */
+#endif /* ASM_X86__XEN__INTERFACE_32_H */