x86: provide specialized identification routines for x86_64

provide two specialized identify_secondary_cpu() and identify_boot_cpu()
routines for x86_64. Although not strictly needed, they are functionally
correct, and will ease integration with i386
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

arch/x86/kernel/setup_64.c

@@ -1036,14 +1036,24 @@ void __cpuinit identify_cpu(struct cpuinfo_x86 *c)
 #endif
 	select_idle_routine(c);
 
-	if (c != &boot_cpu_data)
-		mtrr_ap_init();
 #ifdef CONFIG_NUMA
 	numa_add_cpu(smp_processor_id());
 #endif
 
 }
 
+void __cpuinit identify_boot_cpu(void)
+{
+	identify_cpu(&boot_cpu_data);
+}
+
+void __cpuinit identify_secondary_cpu(struct cpuinfo_x86 *c)
+{
+	BUG_ON(c == &boot_cpu_data);
+	identify_cpu(c);
+	mtrr_ap_init();
+}
+
 static __init int setup_noclflush(char *arg)
 {
 	setup_clear_cpu_cap(X86_FEATURE_CLFLSH);