x86: move prefill_possible_map calling early

call it right after we are done with MADT/mptable handling, instead of
doing that in setup_per_cpu_areas() later on...

this way for_possible_cpu() can be used early.

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/asm-x86/smp.h b/include/asm-x86/smp.h
index fad45f6..b324a06 100644
--- a/include/asm-x86/smp.h
+++ b/include/asm-x86/smp.h
@@ -119,6 +119,10 @@
 {
 	return cpus_weight(cpu_callout_map);
 }
+#else
+static inline void prefill_possible_map(void)
+{
+}
 #endif /* CONFIG_SMP */
 
 extern unsigned disabled_cpus __cpuinitdata;