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/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 314fe0d..5391631 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -1360,9 +1360,8 @@
 				acpi_ioapic = 1;
 
 				smp_found_config = 1;
-#ifdef CONFIG_X86_32
-				setup_apic_routing();
-#endif
+				if (apic->setup_apic_routing)
+					apic->setup_apic_routing();
 			}
 		}
 		if (error == -EINVAL) {