Add SSL_shutdown to SSL_get_error's documentation
Add SSL_shutdown to SSL_get_error's documentation

SSL_shutdown can fail if called during initialization, and in such case, it'll
add an error to the error queue. This adds SSL_shutdown to the list of functions
that should preceed the call to SSL_get_error.

CLA: trivial

Reviewed-by: Matt Caswell <1fa2ef4755a9226cb9a0a4840bd89b158ac71391@openssl.org>
Reviewed-by: Tomas Mraz <973cc78d8b4cb00714230ba9be0225e917ab4ac6@fedoraproject.org>
(Merged from https://github.com/openssl/openssl/pull/7465)

openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl