mdns: Fix fuzzer IDF-mock layer

Removed lwip dependencies
Simplified the mocks for esp32 and esp-netif


* Original commit: espressif/esp-idf@619235c2ee

components/mdns/test_afl_fuzz_host/esp_netif_mock.c

@@ -0,0 +1,63 @@
+// Copyright 2020 Espressif Systems (Shanghai) CO LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <stdio.h>
+#include <string.h>
+#include <pthread.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include "esp32_mock.h"
+
+typedef struct esp_netif_s esp_netif_t;
+typedef struct esp_netif_ip_info esp_netif_ip_info_t;
+typedef struct esp_netif_dhcp_status esp_netif_dhcp_status_t;
+
+
+const char * IP_EVENT = "IP_EVENT";
+
+
+esp_err_t esp_netif_add_to_list(esp_netif_t *netif)
+{
+    return ESP_OK;
+}
+
+esp_err_t esp_netif_remove_from_list(esp_netif_t *netif)
+{
+    return ESP_ERR_NOT_FOUND;
+}
+
+esp_netif_t* esp_netif_next(esp_netif_t* netif)
+{
+    return NULL;
+}
+
+esp_netif_t* esp_netif_next_unsafe(esp_netif_t* netif)
+{
+    return NULL;
+}
+
+esp_netif_t *esp_netif_get_handle_from_ifkey(const char *if_key)
+{
+    return NULL;
+}
+
+esp_err_t esp_netif_get_ip_info(esp_netif_t *esp_netif, esp_netif_ip_info_t *ip_info)
+{
+    return ESP_ERR_NOT_SUPPORTED;
+}
+
+esp_err_t esp_netif_dhcpc_get_status(esp_netif_t *esp_netif, esp_netif_dhcp_status_t *status)
+{
+    return ESP_ERR_NOT_SUPPORTED;
+}