Import mbedtls-2.16.0

Imports mbedTLS 2.16.0 from https://github.com/ARMmbed/mbedtls.git
commit fb1972db23da ("Merge pull request #544 from ARMmbed/version-2.16")
(tag mbedtls-2.16.0).

Certain files will never be needed and are thus removed (reducing number
of lines to almost 50%):
rm -f circle.yml CMakeLists.txt DartConfiguration.tcl Makefile
rm -f .gitignore .travis.yml .pylint
rm -f include/.gitignore include/CMakeLists.txt library/.gitignore
rm -f library/CMakeLists.txt library/Makefile
rm -rf .git .github doxygen configs programs scripts tests visualc yotta

This is a complete overwrite of previous code so earlier changes in the
branch import/mbedtls-2.6.1 will be added on top of this commit to bring
the changes forward.

Acked-by: Jerome Forissier <jerome.forissier@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
diff --git a/lib/libmbedtls/mbedtls/library/certs.c b/lib/libmbedtls/mbedtls/library/certs.c
index bac9e3b..ff0f11e 100644
--- a/lib/libmbedtls/mbedtls/library/certs.c
+++ b/lib/libmbedtls/mbedtls/library/certs.c
@@ -1,8 +1,8 @@
-// SPDX-License-Identifier: Apache-2.0
 /*
  *  X.509 test certificates
  *
  *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
+ *  SPDX-License-Identifier: Apache-2.0
  *
  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
  *  not use this file except in compliance with the License.
@@ -218,12 +218,13 @@
 const char mbedtls_test_ca_pwd_rsa[] = "PolarSSLTest";
 const size_t mbedtls_test_ca_pwd_rsa_len = sizeof( mbedtls_test_ca_pwd_rsa ) - 1;
 
+/* tests/data_files/server2.crt */
 const char mbedtls_test_srv_crt_rsa[] =
 "-----BEGIN CERTIFICATE-----\r\n"
 "MIIDNzCCAh+gAwIBAgIBAjANBgkqhkiG9w0BAQUFADA7MQswCQYDVQQGEwJOTDER\r\n"
-"MA8GA1UEChMIUG9sYXJTU0wxGTAXBgNVBAMTEFBvbGFyU1NMIFRlc3QgQ0EwHhcN\r\n"
+"MA8GA1UECgwIUG9sYXJTU0wxGTAXBgNVBAMMEFBvbGFyU1NMIFRlc3QgQ0EwHhcN\r\n"
 "MTEwMjEyMTQ0NDA2WhcNMjEwMjEyMTQ0NDA2WjA0MQswCQYDVQQGEwJOTDERMA8G\r\n"
-"A1UEChMIUG9sYXJTU0wxEjAQBgNVBAMTCWxvY2FsaG9zdDCCASIwDQYJKoZIhvcN\r\n"
+"A1UECgwIUG9sYXJTU0wxEjAQBgNVBAMMCWxvY2FsaG9zdDCCASIwDQYJKoZIhvcN\r\n"
 "AQEBBQADggEPADCCAQoCggEBAMFNo93nzR3RBNdJcriZrA545Do8Ss86ExbQWuTN\r\n"
 "owCIp+4ea5anUrSQ7y1yej4kmvy2NKwk9XfgJmSMnLAofaHa6ozmyRyWvP7BBFKz\r\n"
 "NtSj+uGxdtiQwWG0ZlI2oiZTqqt0Xgd9GYLbKtgfoNkNHC1JZvdbJXNG6AuKT2kM\r\n"
@@ -231,16 +232,17 @@
 "hYvai0Re4hjGYi/HZo36Xdh98yeJKQHFkA4/J/EwyEoO79bex8cna8cFPXrEAjya\r\n"
 "HT4P6DSYW8tzS1KW2BGiLICIaTla0w+w3lkvEcf36hIBMJcCAwEAAaNNMEswCQYD\r\n"
 "VR0TBAIwADAdBgNVHQ4EFgQUpQXoZLjc32APUBJNYKhkr02LQ5MwHwYDVR0jBBgw\r\n"
-"FoAUtFrkpbPe0lL2udWmlQ/rPrzH/f8wDQYJKoZIhvcNAQEFBQADggEBAJxnXClY\r\n"
-"oHkbp70cqBrsGXLybA74czbO5RdLEgFs7rHVS9r+c293luS/KdliLScZqAzYVylw\r\n"
-"UfRWvKMoWhHYKp3dEIS4xTXk6/5zXxhv9Rw8SGc8qn6vITHk1S1mPevtekgasY5Y\r\n"
-"iWQuM3h4YVlRH3HHEMAD1TnAexfXHHDFQGe+Bd1iAbz1/sH9H8l4StwX6egvTK3M\r\n"
-"wXRwkKkvjKaEDA9ATbZx0mI8LGsxSuCqe9r9dyjmttd47J1p1Rulz3CLzaRcVIuS\r\n"
-"RRQfaD8neM9c1S/iJ/amTVqJxA1KOdOS5780WhPfSArA+g4qAmSjelc3p4wWpha8\r\n"
-"zhuYwjVuX6JHG0c=\r\n"
+"FoAUtFrkpbPe0lL2udWmlQ/rPrzH/f8wDQYJKoZIhvcNAQEFBQADggEBAAFzC0rF\r\n"
+"y6De8WMcdgQrEw3AhBHFjzqnxZw1ene4IBSC7lTw8rBSy3jOWQdPUWn+0y/pCeeF\r\n"
+"kti6sevFdl1hLemGtd4q+T9TKEKGg3ND4ARfB5AUZZ9uEHq8WBkiwus5clGS17Qd\r\n"
+"dS/TOisB59tQruLx1E1bPLtBKyqk4koC5WAULJwfpswGSyWJTpYwIpxcWE3D2tBu\r\n"
+"UB6MZfXZFzWmWEOyKbeoXjXe8GBCGgHLywvYDsGQ36HSGtEsAvR2QaTLSxWYcfk1\r\n"
+"fbDn4jSWkb4yZy1r01UEigFQtONieGwRFaUqEcFJHJvEEGVgh9keaVlOj2vrwf5r\r\n"
+"4mN4lW7gLdenN6g=\r\n"
 "-----END CERTIFICATE-----\r\n";
 const size_t mbedtls_test_srv_crt_rsa_len = sizeof( mbedtls_test_srv_crt_rsa );
 
+/* tests/data_files/server2.key */
 const char mbedtls_test_srv_key_rsa[] =
 "-----BEGIN RSA PRIVATE KEY-----\r\n"
 "MIIEpAIBAAKCAQEAwU2j3efNHdEE10lyuJmsDnjkOjxKzzoTFtBa5M2jAIin7h5r\r\n"
@@ -271,11 +273,12 @@
 "-----END RSA PRIVATE KEY-----\r\n";
 const size_t mbedtls_test_srv_key_rsa_len = sizeof( mbedtls_test_srv_key_rsa );
 
+/* tests/data_files/cli-rsa-sha256.crt */
 const char mbedtls_test_cli_crt_rsa[] =
 "-----BEGIN CERTIFICATE-----\r\n"
-"MIIDhTCCAm2gAwIBAgIBBDANBgkqhkiG9w0BAQsFADA7MQswCQYDVQQGEwJOTDER\r\n"
+"MIIDPzCCAiegAwIBAgIBBDANBgkqhkiG9w0BAQsFADA7MQswCQYDVQQGEwJOTDER\r\n"
 "MA8GA1UECgwIUG9sYXJTU0wxGTAXBgNVBAMMEFBvbGFyU1NMIFRlc3QgQ0EwHhcN\r\n"
-"MTcwNTA1MTMwNzU5WhcNMjcwNTA2MTMwNzU5WjA8MQswCQYDVQQGEwJOTDERMA8G\r\n"
+"MTEwMjEyMTQ0NDA2WhcNMjEwMjEyMTQ0NDA2WjA8MQswCQYDVQQGEwJOTDERMA8G\r\n"
 "A1UECgwIUG9sYXJTU0wxGjAYBgNVBAMMEVBvbGFyU1NMIENsaWVudCAyMIIBIjAN\r\n"
 "BgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAyHTEzLn5tXnpRdkUYLB9u5Pyax6f\r\n"
 "M60Nj4o8VmXl3ETZzGaFB9X4J7BKNdBjngpuG7fa8H6r7gwQk4ZJGDTzqCrSV/Uu\r\n"
@@ -283,18 +286,18 @@
 "MjDV0/YI0FZPRo7yX/k9Z5GIMC5Cst99++UMd//sMcB4j7/Cf8qtbCHWjdmLao5v\r\n"
 "4Jv4EFbMs44TFeY0BGbH7vk2DmqV9gmaBmf0ZXH4yqSxJeD+PIs1BGe64E92hfx/\r\n"
 "/DZrtenNLQNiTrM9AM+vdqBpVoNq0qjU51Bx5rU2BXcFbXvI5MT9TNUhXwIDAQAB\r\n"
-"o4GSMIGPMB0GA1UdDgQWBBRxoQBzckAvVHZeM/xSj7zx3WtGITBjBgNVHSMEXDBa\r\n"
-"gBS0WuSls97SUva51aaVD+s+vMf9/6E/pD0wOzELMAkGA1UEBhMCTkwxETAPBgNV\r\n"
-"BAoMCFBvbGFyU1NMMRkwFwYDVQQDDBBQb2xhclNTTCBUZXN0IENBggEAMAkGA1Ud\r\n"
-"EwQCMAAwDQYJKoZIhvcNAQELBQADggEBAC7yO786NvcHpK8UovKIG9cB32oSQQom\r\n"
-"LoR0eHDRzdqEkoq7yGZufHFiRAAzbMqJfogRtxlrWAeB4y/jGaMBV25IbFOIcH2W\r\n"
-"iCEaMMbG+VQLKNvuC63kmw/Zewc9ThM6Pa1Hcy0axT0faf1B/U01j0FIcw/6mTfK\r\n"
-"D8w48OIwc1yr0JtutCVjig5DC0yznGMt32RyseOLcUe+lfq005v2PAiCozr5X8rE\r\n"
-"ofGZpiM2NqRPePgYy+Vc75Zk28xkRQq1ncprgQb3S4vTsZdScpM9hLf+eMlrgqlj\r\n"
-"c5PLSkXBeLE5+fedkyfTaLxxQlgCpuoOhKBm04/R1pWNzUHyqagjO9Q=\r\n"
+"o00wSzAJBgNVHRMEAjAAMB0GA1UdDgQWBBRxoQBzckAvVHZeM/xSj7zx3WtGITAf\r\n"
+"BgNVHSMEGDAWgBS0WuSls97SUva51aaVD+s+vMf9/zANBgkqhkiG9w0BAQsFAAOC\r\n"
+"AQEAlHabem2Tu69VUN7EipwnQn1dIHdgvT5i+iQHpSxY1crPnBbAeSdAXwsVEqLQ\r\n"
+"gOOIAQD5VIITNuoGgo4i+4OpNh9u7ZkpRHla+/swsfrFWRRbBNP5Bcu74AGLstwU\r\n"
+"zM8gIkBiyfM1Q1qDQISV9trlCG6O8vh8dp/rbI3rfzo99BOHXgFCrzXjCuW4vDsF\r\n"
+"r+Dao26bX3sJ6UnEWg1H3o2x6PpUcvQ36h71/bz4TEbbUUEpe02V4QWuL+wrhHJL\r\n"
+"U7o3SVE3Og7jPF8sat0a50YUWhwEFI256m02KAXLg89ueUyYKEr6rNwhcvXJpvU9\r\n"
+"giIVvd0Sbjjnn7NC4VDbcXV8vw==\r\n"
 "-----END CERTIFICATE-----\r\n";
 const size_t mbedtls_test_cli_crt_rsa_len = sizeof( mbedtls_test_cli_crt_rsa );
 
+/* tests/data_files/cli-rsa.key */
 const char mbedtls_test_cli_key_rsa[] =
 "-----BEGIN RSA PRIVATE KEY-----\r\n"
 "MIIEpAIBAAKCAQEAyHTEzLn5tXnpRdkUYLB9u5Pyax6fM60Nj4o8VmXl3ETZzGaF\r\n"