Fix ainfo with keyword arguments; fix #4921

mrbgems/mruby-compiler/core/codegen.c

@@ -771,7 +771,7 @@ lambda_body(codegen_scope *s, node *tree, int blk)
     s->ainfo = (((ma+oa) & 0x3f) << 7) /* (12bits = 5:1:5:1) */
       | ((ra & 0x1) << 6)
       | ((pa & 0x1f) << 1)
-      | (kd & 0x1);
+      | ((ka | kd) != 0 ? 0x01 : 0x00);
     genop_W(s, OP_ENTER, a);
     /* generate jump table for optional arguments initializer */
     pos = new_label(s);