rework ddlist

src/lv_misc/lv_mem.c

@@ -356,7 +356,8 @@ lv_res_t lv_mem_test(void)
     lv_mem_ent_t * e;
     e = ent_get_next(NULL);
     while(e) {
-        if(e->header.s.d_size > 20000) {
+        if((e->header.s.used && e->header.s.d_size > 20000) ||
+            (e->header.s.used == 0 && e->header.s.d_size > LV_MEM_SIZE)) {
             printf("mem err\n");
             while(1);
             return LV_RES_INV;