disable obsolete 64bit code

arch/x86/kernel/apic.c

@@ -299,7 +299,9 @@ extern void smp_entry(void);
 
 void smp_start(uint32_t id)
 {
+#ifdef CONFIG_X86_32
 	size_t i;
+#endif
 
 	atomic_int32_inc(&cpu_online);
 
@@ -318,6 +320,8 @@ void smp_start(uint32_t id)
 	// install IDT
 	idt_install();
 
+	// On 64bit system, paging is already enabled
+#ifdef CONFIG_X86_32
 	/* enable paging */
 	write_cr3((size_t)get_boot_pgd());
 	i = read_cr0();
@@ -327,6 +331,7 @@ void smp_start(uint32_t id)
 	// reset APIC and set id
 	lapic_reset(); // sets also the timer interrupt
 	apic_set_cpu_id(id);
+#endif
 
 	/*
 	 * we turned on paging