Fix ERR_print_errors so that it matches the documented format in doc/man3/ERR_error_string.pod

Fixes #11743

The ouput format had 2 issues that caused it not to match the expected documented format:
(1) At some point the thread id printing was changed to use the OPENSSL_hex2str method which puts ':' between hex bytes.
    An internal function that skips the seperator has been added.
(2) The error code no longer exists. So this was completely removed from the string. It is now replaced by ::

As an example:
  00:77:6E:52:14:7F:00:00:error:asn1 encoding routines:asn1_check_tlen:wrong tag:crypto/asn1/tasn_dec.c:1135:
Is now:
  00776E52147F0000:error::asn1 encoding routines:asn1_check_tlen:wrong tag:crypto/asn1/tasn_dec.c:1135:

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/11789)

1 files changed, 15 insertions, 0 deletions

diff --git a/test/recipes/04-test_hexstring.t b/test/recipes/04-test_hexstring.t
new file mode 100644
index 0000000000..664868fe60
--- /dev/null
+++ b/test/recipes/04-test_hexstring.t
@@ -0,0 +1,15 @@
+#! /usr/bin/env perl
+# Copyright 2020 The OpenSSL Project Authors. All Rights Reserved.
+#
+# Licensed under the Apache License 2.0 (the "License").  You may not use
+# this file except in compliance with the License.  You can obtain a copy
+# in the file LICENSE in the source distribution or at
+# https://www.openssl.org/source/license.html
+
+use strict;
+use OpenSSL::Test;
+use OpenSSL::Test::Simple;
+
+setup("test_hexstring");
+
+simple_test("test_hexstring", "hexstr_test");