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/processor.h b/arch/x86/include/asm/processor.h
index ee7cbb3..5ca01e3 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -1,5 +1,5 @@
-#ifndef ASM_X86__PROCESSOR_H
-#define ASM_X86__PROCESSOR_H
+#ifndef _ASM_X86_PROCESSOR_H
+#define _ASM_X86_PROCESSOR_H
 
 #include <asm/processor-flags.h>
 
@@ -933,4 +933,4 @@
 extern int get_tsc_mode(unsigned long adr);
 extern int set_tsc_mode(unsigned int val);
 
-#endif /* ASM_X86__PROCESSOR_H */
+#endif /* _ASM_X86_PROCESSOR_H */