x86: fully honor "nolapic", fix

Impact: build fix

Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/apic.c b/arch/x86/kernel/apic.c
index 4857879..9ca12af 100644
--- a/arch/x86/kernel/apic.c
+++ b/arch/x86/kernel/apic.c
@@ -1131,7 +1131,9 @@
 	int i, j;
 
 	if (disable_apic) {
+#ifdef CONFIG_X86_IO_APIC
 		disable_ioapic_setup();
+#endif
 		return;
 	}