Attempt to support pre-1.1.0 openssl.
Attempt to support pre-1.1.0 openssl.

Despite that the website claims that "these functions are available in
all versions of OpenSSL."

Signed-off-by: Patrick Vacek <a38520cbbe2e974bc8b7ea86877dd3c7115ca2d7@gmail.com>

advancedtelematic/aktualizr,advancedtelematic/aktualizr,advancedtelematic/aktualizr,advancedtelematic/aktualizr