Merge mbedtls 2.16.6 into baremetal

Conflicts:
mbedtls.doxyfile - PROJECT_NAME - mbed TLS v2.16.6 chosen.
doc_mainpage.h - mbed TLS v2.16.6 version chosen.
hmac_drbg.h - line 260, extended description chosen.
            - line 313, extended description chosen.
            - line 338, extended description chosen.
version.h - 2.16.6 chosen.
CMakeLists.txt - 2.16.6 chosen.
test_suite_version.data - 2.16.6 chosen.
Makefile - 141 - manual correction - baremetal version of C_SOURCE_FILES
                 with variables for directories plus 2.16.6 CTAGS addition.
pkparse.c - lines 846 onwards - the asn1_get_nonzero_mpi implementation chosen.
ssl_tls.c - line 5269 - edited manually, left the ret=0, because baremetal has
            a different behaviour since commit 87b5626, but added a debug
            message that's new in 2.16.6.    
all.sh:
- component_build_deprecated - chosen the refactored version from 2.16.6,
                               but with extra flags from baremetal.
- rest of the _no_xxx tests - merged make options to have PTHREAD=1 and
                              other changes from 2.16.6 (like -O1 instead of -O0).
- component_build_arm_none_eabi_gcc_no_64bit_multiplication - added 
                              TINYCRYPT_BUILD=0 to the 2.16.6 version of make.

x509/req_app.c - left baremetal log but with mbedtls_exit( 0 ) call.
x509/crl_app.c - left baremetal log but with mbedtls_exit( 0 ) call.
x509/cert_app.c - left baremetal log but with mbedtls_exit( 0 ) call.
ssl/ssl_mail_client.c - left baremetal log but with mbedtls_exit( 0 ) call.
ssl/ssl_pthread_server.c - left baremetal log but with mbedtls_exit( 0 ) call.
ssl/ssl_fork_server.c - left baremetal log but with mbedtls_exit( 0 ) call.
ssl_client1.c - line 54 - left baremetal log but with mbedtls_exit( 0 ) call.
ssl_client2.c - line 54 - left baremetal log but with mbedtls_exit( 0 ) call.
              - line 132 - new options of both branches added.
              - skip close notify handled as in 2.16.6, but with `ssl` instead of `&ssl`.
              - Merged the 2.16.6 usage split with additional baremetal usages.
              - Merged options from baremetal and 2.16.6.
ssl_server.c - left baremetal log but with mbedtls_exit( 0 ) call.
ssl_server2.c - Merged the 2.16.6 usage split with additional baremetal usages.
config.pl - fixed missing defines from the documentation, removed duplicates,
            and reorganised so that the documentation and excluded list
            are ordered in the same way.
test_suite_x509parse.data - only added the two new pathlen tests.
x509_crt.c - change the return code by removing
             MBEDTLS_ERR_X509_INVALID_EXTENSIONS, since it's added by
             x509_crt_frame_parse_ext not by an "or", but by "+=".
Changelog - Assigned all entries to appropriate sections.
ssl-opt.sh - line 8263 - merged options.
           - removed lines 1165 - 1176 - there was a duplicate test, probably
             an artifact of previous merges.
check-files.py - sticked to old formatting.

Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
diff --git a/tests/scripts/test_generate_test_code.py b/tests/scripts/test_generate_test_code.py
index 6d7113e..c8e8c5c 100755
--- a/tests/scripts/test_generate_test_code.py
+++ b/tests/scripts/test_generate_test_code.py
@@ -294,7 +294,7 @@
         self.assertEqual(code, expected)
 
 
-class StringIOWrapper(StringIO, object):
+class StringIOWrapper(StringIO):
     """
     file like class to mock file object in tests.
     """
@@ -1127,9 +1127,8 @@
 dhm_selftest:
 """
         stream = StringIOWrapper('test_suite_ut.function', data)
-        tests = [(name, test_function, dependencies, args)
-                 for name, test_function, dependencies, args in
-                 parse_test_data(stream)]
+        # List of (name, function_name, dependencies, args)
+        tests = list(parse_test_data(stream))
         test1, test2, test3, test4 = tests
         self.assertEqual(test1[0], 'Diffie-Hellman full exchange #1')
         self.assertEqual(test1[1], 'dhm_do_dhm')
@@ -1170,9 +1169,8 @@
 
 """
         stream = StringIOWrapper('test_suite_ut.function', data)
-        tests = [(name, function_name, dependencies, args)
-                 for name, function_name, dependencies, args in
-                 parse_test_data(stream)]
+        # List of (name, function_name, dependencies, args)
+        tests = list(parse_test_data(stream))
         test1, test2 = tests
         self.assertEqual(test1[0], 'Diffie-Hellman full exchange #1')
         self.assertEqual(test1[1], 'dhm_do_dhm')