x86: provide bogus hard_smp_processor_id

We provide a bogus macro for x86_64 in case CONFIG_X86_LOCAL_APIC
is not set. It will always be set for x86_64, so the effect
is just to make the code equal to i386.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

include/asm-x86/smp_64.h

@@ -46,6 +46,8 @@ static inline int num_booting_cpus(void)
 
 #define safe_smp_processor_id()		smp_processor_id()
 
+#ifdef CONFIG_X86_LOCAL_APIC
+
 static inline int logical_smp_processor_id(void)
 {
 	/* we don't want to mark this access volatile - bad code generation */
@@ -63,5 +65,13 @@ static inline int hard_smp_processor_id(void)
 }
 # endif /* APIC_DEFINITION */
 
+#else /* CONFIG_X86_LOCAL_APIC */
+
+# ifndef CONFIG_SMP
+#  define hard_smp_processor_id()	0
+# endif
+
+#endif /* CONFIG_X86_LOCAL_APIC */
+
 #endif