Merge branch 'development' into iotssl-1260-non-blocking-ecc-restricted

* development: (180 commits)
  Change the library version to 2.11.0
  Fix version in ChangeLog for fix for #552
  Add ChangeLog entry for clang version fix. Issue #1072
  Compilation warning fixes on 32b platfrom with IAR
  Revert "Turn on MBEDTLS_SSL_ASYNC_PRIVATE by default"
  Fix for missing len var when XTS config'd and CTR not
  ssl_server2: handle mbedtls_x509_dn_gets failure
  Fix harmless use of uninitialized memory in ssl_parse_encrypted_pms
  SSL async tests: add a few test cases for error in decrypt
  Fix memory leak in ssl_server2 with SNI + async callback
  SNI + SSL async callback: make all keys async
  ssl_async_resume: free the operation context on error
  ssl_server2: get op_name from context in ssl_async_resume as well
  Clarify "as directed here" in SSL async callback documentation
  SSL async callbacks documentation: clarify resource cleanup
  Async callback: use mbedtls_pk_check_pair to compare keys
  Rename mbedtls_ssl_async_{get,set}_data for clarity
  Fix copypasta in the async callback documentation
  SSL async callback: cert is not always from mbedtls_ssl_conf_own_cert
  ssl_async_set_key: detect if ctx->slots overflows
  ...
diff --git a/include/mbedtls/error.h b/include/mbedtls/error.h
index 29c1c21..2a606ad 100644
--- a/include/mbedtls/error.h
+++ b/include/mbedtls/error.h
@@ -4,7 +4,7 @@
  * \brief Error to string translation
  */
 /*
- *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
+ *  Copyright (C) 2006-2018, ARM Limited, All Rights Reserved
  *  SPDX-License-Identifier: Apache-2.0
  *
  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -89,8 +89,9 @@
  * RSA       4   11
  * ECP       4   10 (Started from top)
  * MD        5   5
+ * HKDF      5   1 (Started from top)
  * CIPHER    6   8
- * SSL       6   22 (Started from top)
+ * SSL       6   23 (Started from top)
  * SSL       7   31
  *
  * Module dependent error code (5 bits 0x.00.-0x.F8.)