... as that is ancient history and not used.

Also known as "status_request" or OCSP stapling, defined in RFC6066
section 8.

Thanks-to: Joe Mason
- for the work-around for the OpenSSL bug.

HAVE_BORINGSSL gets defined now by configure and should be defined by
other build systems in case a BoringSSL build is desired.

Commit 7a8b2885 made some functions static and removed the public
Curl_ prefix. Unfortunately, it also removed the sasl_ prefix, which
is the naming convention we use in this source file.

packages/vms/gnv_link_curl.com was assuming only a single letter suffix
in the openssl version.  That assumption has been fixed for 7.40.

curl_sasl.c:1453: warning C4101: 'serverdata' : unreferenced local
                  variable

curl_sasl.c:1221: error C2065: 'mechtable' : undeclared identifier

This error could also happen for non-SSPI builds when cryptography is
disabled (CURL_DISABLE_CRYPTO_AUTH is defined).

Reported-by: Chris Young

There is an issue with conflicting "struct timeval" definitions with
certain AmigaOS releases and C libraries, depending on what gets
included when.  It's a minor difference - the OS one is unsigned,
whereas the common structure has signed elements.  If the OS one ends up
getting defined, this causes a timing calculation error in curl.

It's easy enough to resolve this at the curl end, by casting the
potentially errorneous calculation to a signed long.

... of the other cert verification checks so that you can set verifyhost
and verifypeer to FALSE and still check the public key.

Bug: http://curl.haxx.se/bug/view.cgi?id=1471
Reported-by: Kyle J. McKay

For consistency with other USE_WIN32_ defines as well as the
USE_OPENLDAP define.

Use a dynamicly allocated buffer for the temporary SPN variable similar
to how the SASL GSS-API code does, rather than using a fixed buffer of
2048 characters.

Carrying on from commit 037cd0d9, removed the following unimplemented
instances of curlssl_close_all():

Curl_axtls_close_all()
Curl_darwinssl_close_all()
Curl_cyassl_close_all()
Curl_gskit_close_all()
Curl_gtls_close_all()
Curl_nss_close_all()
Curl_polarssl_close_all()

Slight code cleanup as the SSL backend #define is mixed up with the API
function setup.

Fixed the following warning and error from commit 3af90a6e when SSL
is not being used:

url.c:2004: warning C4013: 'Curl_ssl_cert_status_request' undefined;
            assuming extern returning int

error LNK2019: unresolved external symbol Curl_ssl_cert_status_request
               referenced in function Curl_setopt

Use the same variable name as other areas of SSPI code.

Use the SECURITY_STATUS typedef rather than a unsigned long for the
QuerySecurityPackageInfo() return and rename the variable as per other
areas of SSPI code.

Missed Curl_read64_be() in commit bb12d444 :(