Add rtc code test

hw/efinix_fpga/simulation/tbs/rtc_code_tb.sv

@@ -0,0 +1,23 @@
+`timescale 1ns/1ps
+
+module rtc_code_tb();
+
+sim_top u_sim_top();
+
+always begin
+    if (
+        u_sim_top.w_cpu_addr == 16'h0 &&
+        u_sim_top.w_cpu_we == '1
+    ) begin
+        if (u_sim_top.w_cpu_data_from_cpu == 8'h6d) begin
+            $display("Good finish!");
+            $finish();
+        end else begin
+            $display("Bad finish!");
+            $finish_and_return(-1);
+        end
+    end
+    # 1;
+end
+
+endmodule