chore: restructure the all common modules

rtl/utils/xchecker.sv

@@ -1,6 +1,12 @@
-
-`ifndef INC_XCHECKER_SV
-`define INC_XCHECKER_SV
+// Copyright (c) 2023-2025 Yuchi Miao <miaoyuchi@ict.ac.cn>
+// common is licensed under Mulan PSL v2.
+// You can use this software according to the terms and conditions of the Mulan PSL v2.
+// You may obtain a copy of Mulan PSL v2 at:
+//             http://license.coscl.org.cn/MulanPSL2
+// THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
+// EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
+// MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
+// See the Mulan PSL v2 for more details.
 
 module xchecker #(
     parameter DATA_WIDTH = 1
@@ -15,4 +21,3 @@ module xchecker #(
     $fatal("\n [error]: detected x value here which can lead to the x state propagation problem\n");
 
 endmodule
-`endif