x86, x2apic: fix clear_local_APIC() in the presence of x2apic

Impact: cleanup, paranoia

We were not clearing the local APIC in clear_local_APIC() in the
presence of x2apic. Fix it.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h
index 394d177..6d5b6f0 100644
--- a/arch/x86/include/asm/apic.h
+++ b/arch/x86/include/asm/apic.h
@@ -184,6 +184,9 @@
 {
 	return 0;
 }
+
+#define	x2apic	0
+
 #endif
 
 extern int get_physical_broadcast(void);