x509-create-sign.cpp: Fix build failure with Openssl 4.0

[LocutusOfBorg]

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[LocutusOfBorg]

OCA signed.

[klaus-vb]

Much appreciated. Looks good to me, and I'll see that it gets integrated.

The second change made me look at how I can test it easily, and I ended up spotting unfinished code and some pre-existing coding style violations... will take care of that in a follow-up change after this one is integrating (hope the OCA signing is ticked off soon).

[LocutusOfBorg]

Hello, for the OCA I don't really know, for the X509_NAME, feel free to avoid the cast, I really don't like it but duplicating the variables just to please gcc was even worse :)

[loqs]

I really don't like it but duplicating the variables just to please gcc was even worse :)

In future OpenSSL versions X509_get_subject_name could return read only memory and with the cast it will compile without error or has upstream OpenSSL committed to not doing this and your approach is considered good practice? Other projects avoided this approach znc/znc@94bcf91 mumble-voip/mumble@1f00fb3. @eworm-de