tcp_client example: support for Linux target.

examples/protocols/sockets/tcp_client/main/tcp_client_main.c

@@ -0,0 +1,27 @@
+/*
+ * SPDX-FileCopyrightText: 2022 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Unlicense OR CC0-1.0
+ */
+#include "nvs_flash.h"
+#include "esp_netif.h"
+#include "protocol_examples_common.h"
+#include "esp_event.h"
+
+
+extern void tcp_client(void);
+
+void app_main(void)
+{
+    ESP_ERROR_CHECK(nvs_flash_init());
+    ESP_ERROR_CHECK(esp_netif_init());
+    ESP_ERROR_CHECK(esp_event_loop_create_default());
+
+    /* This helper function configures Wi-Fi or Ethernet, as selected in menuconfig.
+     * Read "Establishing Wi-Fi or Ethernet Connection" section in
+     * examples/protocols/README.md for more information about this function.
+     */
+    ESP_ERROR_CHECK(example_connect());
+
+    tcp_client();
+}