bootloader_support: Rename include_priv directory to include_bootloader

Old rationale for "priv" no longer applies.

As reported here: https://esp32.com/viewtopic.php?f=13&t=6155&p=27151#p26601

components/bootloader_support/include_bootloader/bootloader_sha.h

@@ -0,0 +1,32 @@
+// Copyright 2017 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.
+#pragma once
+
+/* Provide a SHA256 API for bootloader_support code,
+   that can be used from bootloader or app code.
+
+   This header is available to source code in the bootloader & bootloader_support components only.
+   Use mbedTLS APIs or include hwcrypto/sha.h to calculate SHA256 in IDF apps.
+*/
+
+#include <stdint.h>
+#include <stdlib.h>
+
+typedef void *bootloader_sha256_handle_t;
+
+bootloader_sha256_handle_t bootloader_sha256_start();
+
+void bootloader_sha256_data(bootloader_sha256_handle_t handle, const void *data, size_t data_len);
+
+void bootloader_sha256_finish(bootloader_sha256_handle_t handle, uint8_t *digest);