qom: add helper macro DEFINE_TYPES()

DEFINE_TYPES() will help to simplify following routine patterns:

static void foo_register_types(void)
{
type_register_static(&foo1_type_info);
type_register_static(&foo2_type_info);
...
}

type_init(foo_register_types)

or

static void foo_register_types(void)
{
int i;

for (i = 0; i < ARRAY_SIZE(type_infos); i++) {
type_register_static(&type_infos[i]);
}
}

type_init(foo_register_types)

with a single line

DEFINE_TYPES(type_infos)

where types have static definition which could be consolidated in
a single array of TypeInfo structures.
It saves us ~6-10LOC per use case and would help to replace
imperative foo_register_types() there with declarative style of
type registration.

Backports commit 38b5d79b2e8cf6085324066d84e8bb3b3bbe8548 from qemu

qemu/include/qom/object.h

@@ -85,6 +85,28 @@ struct uc_struct;
  * #TypeInfo describes information about the type including what it inherits
  * from, the instance and class size, and constructor/destructor hooks.
  *
+ * Alternatively several static types could be registered using helper macro
+ * DEFINE_TYPES()
+ *
+ * <example>
+ *   <programlisting>
+ * static const TypeInfo device_types_info[] = {
+ *     {
+ *         .name = TYPE_MY_DEVICE_A,
+ *         .parent = TYPE_DEVICE,
+ *         .instance_size = sizeof(MyDeviceA),
+ *     },
+ *     {
+ *         .name = TYPE_MY_DEVICE_B,
+ *         .parent = TYPE_DEVICE,
+ *         .instance_size = sizeof(MyDeviceB),
+ *     },
+ * };
+ *
+ * DEFINE_TYPES(device_types_info)
+ *   </programlisting>
+ * </example>
+ *
  * Every type has an #ObjectClass associated with it.  #ObjectClass derivatives
  * are instantiated dynamically but there is only ever one instance for any
  * given type.  The #ObjectClass typically holds a table of function pointers
@@ -685,6 +707,20 @@ Type type_register(struct uc_struct *uc, const TypeInfo *info);
  */
 void type_register_static_array(struct uc_struct *uc, const TypeInfo *infos, int nr_infos);
 
+/**
+ * DEFINE_TYPES:
+ * @type_array: The array containing #TypeInfo structures to register
+ *
+ * @type_array should be static constant that exists for the life time
+ * that the type is registered.
+ */
+#define DEFINE_TYPES(type_array)                                            \
+static void do_qemu_init_ ## type_array(struct uc_struct *uc)               \
+{                                                                           \
+    type_register_static_array(uc, type_array, ARRAY_SIZE(type_array));     \
+}                                                                           \
+type_init(do_qemu_init_ ## type_array)
+
 /**
  * object_class_dynamic_cast_assert:
  * @klass: The #ObjectClass to attempt to cast.