x86: cleanup unused compat_apic_id_mode

commit
  f862ddb (hw/i386: Remove the deprecated pc-1.x machine types)
removed the last user of broken APIC ID compat knob,
but compat_apic_id_mode itself was forgotten.
Clean it up and simplify x86_cpu_apic_id_from_index()

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <20220228131634.3389805-1-imammedo@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

hw/i386/x86.c

@@ -83,24 +83,11 @@ inline void init_topo_info(X86CPUTopoInfo *topo_info,
 uint32_t x86_cpu_apic_id_from_index(X86MachineState *x86ms,
                                     unsigned int cpu_index)
 {
-    X86MachineClass *x86mc = X86_MACHINE_GET_CLASS(x86ms);
     X86CPUTopoInfo topo_info;
-    uint32_t correct_id;
-    static bool warned;
 
     init_topo_info(&topo_info, x86ms);
 
-    correct_id = x86_apicid_from_cpu_idx(&topo_info, cpu_index);
-    if (x86mc->compat_apic_id_mode) {
-        if (cpu_index != correct_id && !warned && !qtest_enabled()) {
-            error_report("APIC IDs set in compatibility mode, "
-                         "CPU topology won't match the configuration");
-            warned = true;
-        }
-        return cpu_index;
-    } else {
-        return correct_id;
-    }
+    return x86_apicid_from_cpu_idx(&topo_info, cpu_index);
 }
 
 
@@ -1330,7 +1317,6 @@ static void x86_machine_class_init(ObjectClass *oc, void *data)
     mc->cpu_index_to_instance_props = x86_cpu_index_to_props;
     mc->get_default_cpu_node_id = x86_get_default_cpu_node_id;
     mc->possible_cpu_arch_ids = x86_possible_cpu_arch_ids;
-    x86mc->compat_apic_id_mode = false;
     x86mc->save_tsc_khz = true;
     x86mc->fwcfg_dma_enabled = true;
     nc->nmi_monitor_handler = x86_nmi;

include/hw/i386/x86.h

@@ -35,8 +35,6 @@ struct X86MachineClass {
 
     /* TSC rate migration: */
     bool save_tsc_khz;
-    /* Enables contiguous-apic-ID mode */
-    bool compat_apic_id_mode;
     /* use DMA capable linuxboot option rom */
     bool fwcfg_dma_enabled;
 };