x86: unify smp_prepare_cpus

definition is moved to common header. x86_64 version is now called
native_smp_prepare_cpus

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/smpboot_64.c b/arch/x86/kernel/smpboot_64.c
index 47e654c..b106983 100644
--- a/arch/x86/kernel/smpboot_64.c
+++ b/arch/x86/kernel/smpboot_64.c
@@ -867,7 +867,7 @@
  * Prepare for SMP bootup.  The MP table or ACPI has been read
  * earlier.  Just do some sanity checking here and enable APIC mode.
  */
-void __init smp_prepare_cpus(unsigned int max_cpus)
+void __init native_smp_prepare_cpus(unsigned int max_cpus)
 {
 	nmi_watchdog_default();
 	smp_cpu_index_default();