x86: make native_machine_shutdown non-static

it will allow external users to call it. It is mainly
useful for routines that will override its machine_ops
field for its own special purposes, but want to call the
normal shutdown routine after they're done
Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

arch/x86/kernel/reboot.c

@@ -399,7 +399,7 @@ static void native_machine_emergency_restart(void)
 	}
 }
 
-static void native_machine_shutdown(void)
+void native_machine_shutdown(void)
 {
 	/* Stop the cpus and apics */
 #ifdef CONFIG_SMP

include/asm-x86/reboot.h

@@ -16,5 +16,6 @@ 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);
 
 #endif	/* _ASM_REBOOT_H */