Remove duplicate cipher entries from TLS translation table.

Patch from trac#304 - the translation table OpenSSL<->IANA contained
duplicates for four IANA names, causing translation backwards to fail.

Signed-off-by: Gert Doering <gert@greenie.muc.de>
Acked-By: Steffan Karger <steffan.karger@fox-it.com>
URL: https://community.openvpn.net/openvpn/ticket/304