x86: replace CONFIG_X86_SMP with CONFIG_SMP

The x86/Voyager subarch used to have this distinction between
 'x86 SMP support' and 'Voyager SMP support':

 config X86_SMP
	bool
	depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)

This is a pointless distinction - Voyager can (and already does) use
smp_ops to implement various SMP quirks it has - and it can be extended
more to cover all the specialities of Voyager.

So remove this complication in the Kconfig space.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index e68bb9e..89537f6 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -344,7 +344,7 @@
 
 void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c)
 {
-#ifdef CONFIG_X86_SMP
+#ifdef CONFIG_SMP
 	if (pm_idle == poll_idle && smp_num_siblings > 1) {
 		printk(KERN_WARNING "WARNING: polling idle and HT enabled,"
 			" performance may degrade.\n");