[ACPI] enable SMP C-states on x86_64

http://bugzilla.kernel.org/show_bug.cgi?id=5653

Signed-off-by: David Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/include/asm-x86_64/acpi.h b/include/asm-x86_64/acpi.h
index aa1c7b2..2c95a31 100644
--- a/include/asm-x86_64/acpi.h
+++ b/include/asm-x86_64/acpi.h
@@ -162,6 +162,8 @@
 
 extern u8 x86_acpiid_to_apicid[];
 
+#define ARCH_HAS_POWER_INIT 1
+
 extern int acpi_skip_timer_override;
 
 #endif /*__KERNEL__*/