x86, apic: clean up ->setup_apic_routing()

- separate the namespace

 - remove macros

 - remove namespace clash on 64-bit

Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/mpparse.c b/arch/x86/kernel/mpparse.c
index fa6bb26..c8a534a 100644
--- a/arch/x86/kernel/mpparse.c
+++ b/arch/x86/kernel/mpparse.c
@@ -390,9 +390,9 @@
        generic_bigsmp_probe();
 #endif
 
-#ifdef CONFIG_X86_32
-	setup_apic_routing();
-#endif
+	if (apic->setup_apic_routing)
+		apic->setup_apic_routing();
+
 	if (!num_processors)
 		printk(KERN_ERR "MPTABLE: no processors registered!\n");
 	return num_processors;