x86: refactor ->check_phys_apicid_present() subarch methods

- spread out the namespace to per driver methods

 - extend it to 64-bit as well so that we can use
   apic->check_phys_apicid_present() unconditionally

Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/include/asm/genapic.h b/arch/x86/include/asm/genapic.h
index 2cb14d5..f292fd0 100644
--- a/arch/x86/include/asm/genapic.h
+++ b/arch/x86/include/asm/genapic.h
@@ -110,6 +110,7 @@
 extern void default_setup_apic_routing(void);
 
 extern int default_cpu_present_to_apicid(int mps_cpu);
+extern int default_check_phys_apicid_present(int boot_cpu_physical_apicid);
 #endif
 
 #endif /* _ASM_X86_GENAPIC_64_H */