NVS: using esp_partition API

* partition api changed from spi_flash* API to
  esp_partition* API and is abstracted as a C++
  interface.
* The old nvs encryption is still possible
* changed default unit test app partition table
* Partitions coming from esp_partition API are
  checked for generic flash encryption. If yes,
  an error is returned since generic flash
  encryption isn't compatible with nvs
  encryption
* esp32, esp32s2 tests don't require nvs_flash
  but mbedtls now

Closes IDF-1340
Closes IDF-858

components/nvs_flash/src/nvs_partition.cpp

@@ -0,0 +1,78 @@
+// Copyright 2019 Espressif Systems (Shanghai) PTE 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 "string.h"
+#include "nvs_partition.hpp"
+
+namespace nvs {
+
+NVSPartition::NVSPartition(const esp_partition_t* partition)
+    : mESPPartition(partition)
+{
+    // ensure the class is in a valid state
+    if (partition == nullptr) {
+        abort();
+    }
+}
+
+const char *NVSPartition::get_partition_name()
+{
+    return mESPPartition->label;
+}
+
+esp_err_t NVSPartition::read_raw(size_t src_offset, void* dst, size_t size)
+{
+    return esp_partition_read_raw(mESPPartition, src_offset, dst, size);
+}
+
+esp_err_t NVSPartition::read(size_t src_offset, void* dst, size_t size)
+{
+    if (size % ESP_ENCRYPT_BLOCK_SIZE != 0) {
+        return ESP_ERR_INVALID_ARG;
+    }
+
+    return esp_partition_read(mESPPartition, src_offset, dst, size);
+}
+
+esp_err_t NVSPartition::write_raw(size_t dst_offset, const void* src, size_t size)
+{
+    return esp_partition_write_raw(mESPPartition, dst_offset, src, size);
+}
+
+esp_err_t NVSPartition::write(size_t dst_offset, const void* src, size_t size)
+{
+    if (size % ESP_ENCRYPT_BLOCK_SIZE != 0) {
+        return ESP_ERR_INVALID_ARG;
+    }
+
+    return esp_partition_write(mESPPartition, dst_offset, src, size);
+}
+
+esp_err_t NVSPartition::erase_range(size_t dst_offset, size_t size)
+{
+    return esp_partition_erase_range(mESPPartition, dst_offset, size);
+}
+
+uint32_t NVSPartition::get_address()
+{
+    return mESPPartition->address;
+}
+
+uint32_t NVSPartition::get_size()
+{
+    return mESPPartition->size;
+}
+
+} // nvs
+