Added fixed labels using nvs in generic_switch example.

Fixes https://github.com/espressif/esp-matter/issues/211
Added two fixed-labels using nvs in the generic_switch example.
Added the mfg generated binary file 20202020_3841.bin to flash at the specified address after flashing the firmware.

examples/generic_switch/README.md

@@ -2,12 +2,33 @@
 
 This example creates a Generic Switch device using the ESP
 Matter data model.
+This example aims to demonstrate the use of Fixed Label Cluster which provides a feature for the device to tag an endpoint with zero or more read-only labels using nvs api.
+
+Note:
+    In order to retrieve the label-list from the fixed-label cluster the two options:
+    ``CONFIG_ENABLE_ESP32_FACTORY_DATA_PROVIDER`` and ``CONFIG_ENABLE_ESP32_DEVICE_INFO_PROVIDER`` have been set through sdkcofig.defaults.
 
 See the [docs](https://docs.espressif.com/projects/esp-matter/en/latest/esp32/developing.html) for more information about building and flashing the firmware.
 
 ## 1. Additional Environment Setup
 
-No additional setup is required.
+The steps below should be followed in order to access the fixed-labels.
+-   If monitoring the device using ``idf.py monitor``,press `` Ctrl + ]`` to stop the process.
+-   The following command must be executed to flash the mfg partition:
+```
+esptool.py -p [port-name] write_flash 0x10000 mfg_binaries/20202020_3841.bin
+```
+-   Execute the command ``idf.py monitor``
+-   Commission the device with ``discriminator: 20202020``and `` passcode: 3841``
+-   Command:
+```
+chip-tool pairing ble-wifi 0x7283 [ssid] [password] 20202020 3841
+```
+-   To read the fixed-labels, use chip-tool.
+-   Command :
+```
+chip-tool fixedlabels read label-list 0x7283 1
+```
 
 ## 2. Post Commissioning Setup
 

examples/generic_switch/main/app_main.cpp

@@ -107,6 +107,9 @@ extern "C" void app_main()
     switch_endpoint_id = endpoint::get_id(endpoint);
     ESP_LOGI(TAG, "Generic Switch created with endpoint_id %d", switch_endpoint_id);
 
+    cluster::fixed_label::config_t fl_config;
+    cluster_t *fl_cluster = cluster::fixed_label::create(endpoint, &fl_config, CLUSTER_FLAG_SERVER);
+
     /* Add additional features to the node */
     cluster_t *cluster = cluster::get(endpoint, Switch::Id);
 #if CONFIG_GENERIC_SWITCH_TYPE_LATCHING
@@ -122,6 +125,22 @@ extern "C" void app_main()
         ESP_LOGE(TAG, "Matter start failed: %d", err);
     }
 
+    nvs_handle_t handle;
+    nvs_open_from_partition(CONFIG_CHIP_FACTORY_NAMESPACE_PARTITION_LABEL, "chip-factory", NVS_READWRITE, &handle);
+
+    int32_t out_value = 0;
+    if (nvs_get_i32(handle, "fl-sz/1", &out_value) == ESP_ERR_NVS_NOT_FOUND)
+    {
+       nvs_set_i32(handle, "fl-sz/1", 2);
+       nvs_set_str(handle, "fl-k/1/0", "myEP1LBL1");
+       nvs_set_str(handle, "fl-v/1/0", "valEP1LBL1");
+       nvs_set_str(handle, "fl-k/1/1", "myEP1LBL2");
+       nvs_set_str(handle, "fl-v/1/1", "valEP1LBL2");
+    }
+
+    nvs_commit(handle);
+    nvs_close(handle);
+
 #if CONFIG_ENABLE_CHIP_SHELL
     esp_matter::console::diagnostics_register_commands();
     esp_matter::console::wifi_register_commands();

examples/generic_switch/sdkconfig.defaults

@@ -36,3 +36,7 @@ CONFIG_ESP_WIFI_SOFTAP_SUPPORT=n
 
 # Disable DS Peripheral
 CONFIG_ESP_SECURE_CERT_DS_PERIPHERAL=n
+
+# Enable for fixed-label
+CONFIG_ENABLE_ESP32_FACTORY_DATA_PROVIDER=y
+CONFIG_ENABLE_ESP32_DEVICE_INFO_PROVIDER=y