Make AEAD modes work with OpenSSL 1.0.1-1.0.1c

Make AEAD modes work with OpenSSL 1.0.1-1.0.1c

The 'nobody uses OpenSSL 1.0.1-1.0.1c'-gamble in commit 66407e11 (add AEAD
support) did not turn out well; apparently Ubuntu 12.04 LTS ships with a
broken OpenSSL 1.0.1.  Since this is still a popular platform, re-add the
fixup code, now with a clear version check so it's easy to remove once we
drop support for OpenSSL 1.0.1.

Signed-off-by: Steffan Karger <steffan@karger.me>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <1457256715-4467-1-git-send-email-steffan@karger.me>
URL: http://article.gmane.org/gmane.network.openvpn.devel/11322
Signed-off-by: Gert Doering <gert@greenie.muc.de>