[openssl/openssl] 9257a8: cms demos: print signingTime attributes

[James Muir]

  Branch: refs/heads/master
  Home:   https://github.com/openssl/openssl
  Commit: 9257a89b6f25dfa5aeee7114baec8ea992fcf5e5
      https://github.com/openssl/openssl/commit/9257a89b6f25dfa5aeee7114baec8ea992fcf5e5
  Author: James Muir <james at openssl.org>
  Date:   2023-11-10 (Fri, 10 Nov 2023)

  Changed paths:
    A demos/cms/Makefile
    M demos/cms/cms_dec.c
    M demos/cms/cms_enc.c
    M demos/cms/cms_sign2.c
    M demos/cms/cms_ver.c

  Log Message:
  -----------
  cms demos: print signingTime attributes

Add a makefile for the cms demos, and add a routine to cms_ver.c to
print any signingTime attributes from the CMS_ContentInfo object.
This provides an example that could be extended if an application
wants to examine the purported signing times.

Part of #8026

Testing:

  $ cd demos/cms
  $ make test

Reviewed-by: Shane Lontis <shane.lontis at oracle.com>
Reviewed-by: Tomas Mraz <tomas at openssl.org>
(Merged from https://github.com/openssl/openssl/pull/22618)