hw/core: Get default_cpu_type calling machine_class_default_cpu_type()

Since commit 62b4a227a33 the default cpu type can come from the
valid_cpu_types[] array. Call the machine_class_default_cpu_type()
instead of accessing MachineClass::default_cpu_type field.

Cc: qemu-stable@nongnu.org
Fixes: 62b4a227a33 ("hw/core: Add machine_class_default_cpu_type()")
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Message-Id: <20250422084114.39499-1-philmd@linaro.org>
(cherry picked from commit d5f241834be1b323ea697a469ff0f1335a1823fe)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

hw/core/machine-qmp-cmds.c

@@ -72,6 +72,7 @@ MachineInfoList *qmp_query_machines(bool has_compat_props, bool compat_props,
 
     for (el = machines; el; el = el->next) {
         MachineClass *mc = el->data;
+        const char *default_cpu_type = machine_class_default_cpu_type(mc);
         MachineInfo *info;
 
         info = g_malloc0(sizeof(*info));
@@ -90,8 +91,8 @@ MachineInfoList *qmp_query_machines(bool has_compat_props, bool compat_props,
         info->numa_mem_supported = mc->numa_mem_supported;
         info->deprecated = !!mc->deprecation_reason;
         info->acpi = !!object_class_property_find(OBJECT_CLASS(mc), "acpi");
-        if (mc->default_cpu_type) {
-            info->default_cpu_type = g_strdup(mc->default_cpu_type);
+        if (default_cpu_type) {
+            info->default_cpu_type = g_strdup(default_cpu_type);
         }
         if (mc->default_ram_id) {
             info->default_ram_id = g_strdup(mc->default_ram_id);

target/ppc/cpu_init.c

@@ -7082,7 +7082,7 @@ ObjectClass *ppc_cpu_class_by_name(const char *name)
     if (strcmp(name, "max") == 0) {
         MachineClass *mc = MACHINE_GET_CLASS(qdev_get_machine());
         if (mc) {
-            return object_class_by_name(mc->default_cpu_type);
+            return object_class_by_name(machine_class_default_cpu_type(mc));
         }
     }
 #endif