misc: Gate sys/idt.h as a whole behind x86 check
diff --git a/common/entry.s2.c b/common/entry.s2.c
index b553083c..9de0697f 100644
--- a/common/entry.s2.c
+++ b/common/entry.s2.c
@@ -21,9 +21,7 @@
#include <pxe/pxe.h>
#include <pxe/tftp.h>
#include <drivers/disk.h>
-#if defined (__x86_64__) || defined (__i386__)
-# include <sys/idt.h>
-#endif
+#include <sys/idt.h>
#include <sys/cpu.h>
struct volume *boot_volume;
diff --git a/common/sys/idt.h b/common/sys/idt.h
index d3a74ad2..e9c2a074 100644
--- a/common/sys/idt.h
+++ b/common/sys/idt.h
@@ -1,6 +1,8 @@
#ifndef SYS__IDT_H__
#define SYS__IDT_H__
+#if defined (__x86_64__) || defined (__i386__)
+
#include <stdint.h>
#include <stddef.h>
@@ -58,3 +60,5 @@ void idt_register_isr(size_t vec, void *handler, uint8_t type);
void flush_irqs(void);
#endif
+
+#endif
