Fix missing initializer warning in gobject/gparam.c:g_param_type_register_static()

gobject/gparam.c: In function ‘g_param_type_register_static’:
gobject/gparam.c:1434:3: error: missing initializer for field ‘value_table’ of ‘GTypeInfo’ {aka ‘struct _GTypeInfo’}
 1434 |   };
      |   ^
In file included from gobject/gvalue.h:26,
                 from gobject/gparam.h:26,
                 from gobject/gparam.c:26:
gobject/gtype.h:1063:26: note: ‘value_table’ declared here
 1063 |   const GTypeValueTable *value_table;
      |                          ^~~~~~~~~~~

gobject/gparam.c

@@ -1431,6 +1431,7 @@ g_param_type_register_static (const gchar              *name,
     0,                             /* instance_size */
     16,                            /* n_preallocs */
     NULL,                          /* instance_init */
+    NULL,                          /* value_table */
   };
   ParamSpecClassInfo *cinfo;