soc: swr-mstr-ctrl: check for device number before port params init

If the peripheral device is not enumerated, device number is stuck at
0. Check device number for 0 before initializing port params.

Change-Id: I444b37d56bebdebf75e8e7554cd435beece6b066

soc/swr-mstr-ctrl.c

@@ -2494,6 +2494,10 @@ static int swrm_init_port_params(struct swr_master *mstr, u32 dev_num,
 		pr_err("%s: Invalid handle to swr controller\n", __func__);
 		return 0;
 	}
+	if (dev_num == 0) {
+		pr_err("%s: Invalid device number 0\n", __func__);
+		return -EINVAL;
+	}
 	for (i = 0; i < SWR_UC_MAX; i++) {
 		for (j = 0; j < num_ports; j++) {
 			port_id_offset = (dev_num - 1) * SWR_MAX_DEV_PORT_NUM + j;