Import mbedtls-2.16.5

Imports Mbed TLS 2.16.5 from https://github.com/ARMmbed/mbedtls.git
commit 0fce215851cc ("Merge pull request #3053 from
yanesca/bump-version-2.16.5") (tag mbedtls-2.16.5).

Certain files will bever be needed and are thus removed:
 rm -f .gitignore .globalrc .pylintrc .travis.yml
 rm -f CMakeLists.txt DartConfiguration.tcl Makefile
 rm -f include/{.gitignore,CMakeLists.txt}
 rm -f library/{.gitignore,CMakeLists.txt,Makefile}
 rm -rf .git .github configs docs doxygen programs scripts tests visualc

This is a complete overwrite of previous code so earlier changes in the
branch import/mbedtls-2.16.0 will be added on top of this commit to bring
the changes forward.

Signed-off-by: Jerome Forissier <jerome@forissier.org>
Acked-by: Jens Wiklander <jens.wiklander@linaro.org>
diff --git a/lib/libmbedtls/mbedtls/library/x509_crl.c b/lib/libmbedtls/mbedtls/library/x509_crl.c
index dc40512..00f8545 100644
--- a/lib/libmbedtls/mbedtls/library/x509_crl.c
+++ b/lib/libmbedtls/mbedtls/library/x509_crl.c
@@ -1,8 +1,8 @@
-// SPDX-License-Identifier: Apache-2.0
 /*
  *  X.509 Certidicate Revocation List (CRL) parsing
  *
  *  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.
@@ -103,17 +103,17 @@
 {
     int ret;
 
+    if( *p == end )
+        return( 0 );
+
     /*
      * crlExtensions           [0]  EXPLICIT Extensions OPTIONAL
      *                              -- if present, version MUST be v2
      */
     if( ( ret = mbedtls_x509_get_ext( p, end, ext, 0 ) ) != 0 )
-    {
-        if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
-            return( 0 );
-
         return( ret );
-    }
+
+    end = ext->p + ext->len;
 
     while( *p < end )
     {