x86: remove mach_apic.h, fix

Use apic_read() instead of open-coded mmio.

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 ce3655a..ccfcd19 100644
--- a/arch/x86/include/asm/genapic.h
+++ b/arch/x86/include/asm/genapic.h
@@ -145,7 +145,7 @@
 {
 	unsigned int reg;
 
-	reg = *(u32 *)(APIC_BASE + APIC_ID);
+	reg = apic_read(APIC_ID);
 
 	return apic->get_apic_id(reg);
 }