tests: drivers: smbus: Enabled smbus test for BTL-S platform

Added overlay for smbus for intel_btl_s_crb platform.

Signed-off-by: Bindu S <bindu.s@intel.com>

Author: bindushree98

tests/drivers/smbus/smbus_api/boards/intel_btl_s_crb.overlay

@@ -0,0 +1,9 @@
+/*
+ * Copyright (c) 2025 Intel Corporation
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+&smbus0 {
+	status = "okay";
+};