Add SSL_OP Flag For TLS Version Selection

[Hyeongon-Kim]

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fix a bug that performs a handshake with tls1.3 even when the tls-version option is set to tlsv1.2 (or tlsv1.1)

[Hyeongon-Kim]

i have checked the old issues,
but i think we should be able to select tls-version clearly for *special situations.
*situations such as implementing and using specific crypto-algorithms based on tls-engine.

[Hyeongon-Kim]

#2722 i added code for this issue

[ralight]

Thank you for this. The issue at #2722 is valid, and I have just added a change for that. What you are proposing here though is not correct in my opinion. The tls version options set a minimum version, whereas your changes set an explicit version.

Is there a reason why setting a minimum version is problematic for engine support?