x86: Fix ASM_X86__ header guards

Change header guards named "ASM_X86__*" to "_ASM_X86_*" since:

a. the double underscore is ugly and pointless.
b. no leading underscore violates namespace constraints.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/arch/x86/include/asm/compat.h b/arch/x86/include/asm/compat.h
index 6732b15..9a9c7bd 100644
--- a/arch/x86/include/asm/compat.h
+++ b/arch/x86/include/asm/compat.h
@@ -1,5 +1,5 @@
-#ifndef ASM_X86__COMPAT_H
-#define ASM_X86__COMPAT_H
+#ifndef _ASM_X86_COMPAT_H
+#define _ASM_X86_COMPAT_H
 
 /*
  * Architecture specific compatibility types
@@ -215,4 +215,4 @@
 	return current_thread_info()->status & TS_COMPAT;
 }
 
-#endif /* ASM_X86__COMPAT_H */
+#endif /* _ASM_X86_COMPAT_H */