openssl: make use of the EVP interface
openssl: make use of the EVP interface

Make use of the EVP interface for the AES-funktion. Using this method
supports the use of different ENGINES in OpenSSL for the AES function
(and the direct call to the AES_encrypt should not be used according to
openssl.org)

libssh2/libssh2,libssh2/libssh2,libssh2/libssh2,libssh2/libssh2