x86: constify data in reboot.c

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/include/asm-x86/reboot.h b/include/asm-x86/reboot.h
index e63741f..206f355 100644
--- a/include/asm-x86/reboot.h
+++ b/include/asm-x86/reboot.h
@@ -14,8 +14,8 @@
 
 extern struct machine_ops machine_ops;
 
-void machine_real_restart(unsigned char *code, int length);
 void native_machine_crash_shutdown(struct pt_regs *regs);
 void native_machine_shutdown(void);
+void machine_real_restart(const unsigned char *code, int length);
 
 #endif	/* _ASM_REBOOT_H */