enhance TensorFlow easyblock to take into account provided OpenSSL dependency

[Flamefire]

(created using eb --new-pr)

[SebastianAchilles]

Test report by @sebastianachilles

Overview of tested easyconfigs (in order)

• FAIL (build issue) TensorFlow-2.6.0-foss-2021a.eb (partial log available at https://gist.github.com/bef0139293467fe8780b55bd69bc17dc)

Build succeeded for 0 out of 1 (1 easyconfigs in total) jrc0728 - Linux centos linux 8.3.2011, x86_64, AMD EPYC 7742 64-Core Processor (zen2), Python 3.6.8 See https://gist.github.com/4a3cce1cc0bc3e9b3f76c2fda19d1fad for a full test report.

[Flamefire]

@akesandgren As there is no further update, can we merge this?

[akesandgren]

I think you should ask @SebastianAchilles , I was just trying to get him to react...

[Flamefire]

Well this was 5 months ago. And as the code is correct as far as I can tell (add the include/library paths for OpenSSL when used) I'd suggest to merge this and improve on it if it later turns out to be required. But I don't think so according to the tests I've done at the time.

[akesandgren]

Going in, thanks @Flamefire!