Remove a redundant condition

class.c

@@ -1349,7 +1349,7 @@ class_descendants_recursive(VALUE klass, VALUE v)
     struct subclass_traverse_data *data = (struct subclass_traverse_data *) v;
 
     if (BUILTIN_TYPE(klass) == T_CLASS && !FL_TEST(klass, FL_SINGLETON)) {
-        if (data->buffer && (data->count < data->maxcount || data->maxcount == -1)) {
+        if (data->buffer && data->count < data->maxcount) {
             data->buffer[data->count] = klass;
         }
         data->count++;
@@ -1383,7 +1383,7 @@ rb_class_descendants(VALUE klass)
     // estimate the count of subclasses
     rb_class_foreach_subclass(klass, class_descendants_recursive, (VALUE) &data);
 
-    // this allocation may cause GC which may reduce the subclasses
+    // the following allocation may cause GC which may change the number of subclasses
     data.buffer = ALLOC_N(VALUE, data.count);
     data.maxcount = data.count;
     data.count = 0;