x86, apic: clean up the cpu_2_logical_apiciddeclaration

extern declarations were scattered in 4 files - consolidate them
into apic.h.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/es7000_32.c b/arch/x86/kernel/es7000_32.c
index cf53a98..3dc4883 100644
--- a/arch/x86/kernel/es7000_32.c
+++ b/arch/x86/kernel/es7000_32.c
@@ -403,7 +403,6 @@
 
 extern void es7000_enable_apic_mode(void);
 extern int apic_version [MAX_APICS];
-extern u8 cpu_2_logical_apicid[];
 extern unsigned int boot_cpu_physical_apicid;
 
 extern int parse_unisys_oem (char *oemptr);
@@ -570,7 +569,7 @@
 #ifdef CONFIG_SMP
 	if (cpu >= nr_cpu_ids)
 		return BAD_APICID;
-	return (int)cpu_2_logical_apicid[cpu];
+	return cpu_2_logical_apicid[cpu];
 #else
 	return logical_smp_processor_id();
 #endif