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/apic.c b/arch/x86/kernel/apic.c
index 81efe86..968c817 100644
--- a/arch/x86/kernel/apic.c
+++ b/arch/x86/kernel/apic.c
@@ -1900,7 +1900,7 @@
 	}
 #endif
 
-#if defined(CONFIG_X86_SMP) || defined(CONFIG_X86_64)
+#if defined(CONFIG_SMP) || defined(CONFIG_X86_64)
 	early_per_cpu(x86_cpu_to_apicid, cpu) = apicid;
 	early_per_cpu(x86_bios_cpu_apicid, cpu) = apicid;
 #endif