[openssl/openssl] 86945b: Fix verify_callback in the openssl s_client/s_serv...

[beldmit]

  Branch: refs/heads/OpenSSL_1_1_1-stable
  Home:   https://github.openssl.org/openssl/openssl
  Commit: 86945b10ccd84f685bd6215bbb00d1e700303e49
      https://github.openssl.org/openssl/openssl/commit/86945b10ccd84f685bd6215bbb00d1e700303e49
  Author: Dmitry Belyavskiy <beldmit at gmail.com>
  Date:   2022-07-20 (Wed, 20 Jul 2022)

  Changed paths:
    M apps/s_cb.c

  Log Message:
  -----------
  Fix verify_callback in the openssl s_client/s_server app

We need to check that error cert is available before printing its data

Reviewed-by: Tomas Mraz <tomas at openssl.org>
Reviewed-by: David von Oheimb <david.von.oheimb at siemens.com>
Reviewed-by: Viktor Dukhovni <viktor at openssl.org>
Reviewed-by: Hugo Landau <hlandau at openssl.org>
(Merged from https://github.com/openssl/openssl/pull/18805)

(cherry picked from commit fad0f80eff188ef938fed614245a56ed56110deb)