aws_iot: fix aws_iot examples without NVS initialization

WiFi used to initialise nvs automatically, but it doesn't now.
see more info: https://github.com/espressif/esp-idf/issues/624

Closes #624

examples/protocols/aws_iot/subscribe_publish/main/subscribe_publish_sample.c

@@ -40,6 +40,9 @@
 #include "esp_vfs_fat.h"
 #include "driver/sdmmc_host.h"
 
+#include "nvs.h"
+#include "nvs_flash.h"
+
 #include "aws_iot_config.h"
 #include "aws_iot_log.h"
 #include "aws_iot_version.h"
@@ -316,6 +319,14 @@ static void initialise_wifi(void)
 
 void app_main()
 {
+    // Initialize NVS.
+    esp_err_t err = nvs_flash_init();
+    if (err == ESP_ERR_NVS_NO_FREE_PAGES) {
+        ESP_ERROR_CHECK(nvs_flash_erase());
+        err = nvs_flash_init();
+    }
+    ESP_ERROR_CHECK( err );
+
     initialise_wifi();
 #ifdef CONFIG_MBEDTLS_DEBUG
     const size_t stack_size = 36*1024;

examples/protocols/aws_iot/thing_shadow/main/thing_shadow_sample.c

@@ -37,6 +37,9 @@
 #include "esp_vfs_fat.h"
 #include "driver/sdmmc_host.h"
 
+#include "nvs.h"
+#include "nvs_flash.h"
+
 #include "aws_iot_config.h"
 #include "aws_iot_log.h"
 #include "aws_iot_version.h"
@@ -362,6 +365,13 @@ static void initialise_wifi(void)
 
 void app_main()
 {
+    esp_err_t err = nvs_flash_init();
+    if (err == ESP_ERR_NVS_NO_FREE_PAGES) {
+        ESP_ERROR_CHECK(nvs_flash_erase());
+        err = nvs_flash_init();
+    }
+    ESP_ERROR_CHECK( err );
+
     initialise_wifi();
     /* Temporarily pin task to core, due to FPU uncertainty */
     xTaskCreatePinnedToCore(&aws_iot_task, "aws_iot_task", 16384+1024, NULL, 5, NULL, 1);