samples: drivers: watchdog: add overlay file for adp_xc7k/ae350/clic

adp_xc7k/ae350/clic uses a different interrupt controller than
adp_xc7k/ae350, add overlay files as in adp_xc7k/ae350.

Signed-off-by: Jimmy Zheng <jimmyzhe@andestech.com>

Author: jimmyzhe

samples/drivers/watchdog/boards/adp_xc7k_ae350_clic.overlay

@@ -0,0 +1,11 @@
+/*
+ * Copyright (c) 2025 Andes Technology Corporation.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/ {
+	aliases {
+		watchdog0 = &wdt;
+	};
+};