x86, apic: clean up ->vector_allocation_domain()

- separate the namespace

 - remove macros

 - move the default vector-allocation-domain to mach-generic

 - fix whitespace damage

Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/io_apic.c b/arch/x86/kernel/io_apic.c
index 733ecf1..49899e0 100644
--- a/arch/x86/kernel/io_apic.c
+++ b/arch/x86/kernel/io_apic.c
@@ -1316,7 +1316,7 @@
 		int new_cpu;
 		int vector, offset;
 
-		vector_allocation_domain(cpu, tmp_mask);
+		apic->vector_allocation_domain(cpu, tmp_mask);
 
 		vector = current_vector;
 		offset = current_offset;