hcrypto: Add hcrypto EVP support to the Unix CM

hcrypto: Add hcrypto EVP support to the Unix CM

This commit adds the files which are necessary to support hcrypto's
EVP interface to the Unix cache manager build. Only a small number
of EVP ciphers and hashes are currently supported -
    * aes_128_cbc
    * aes_256_cbc
    * sha1

Note that the EVP interface is the only supported mechanism to use
the AES cipher - directly calling the underlying crypto functions
is not recommended and may break at any time.

Change-Id: I662073e578b29db1707c6b6433209e75e4db455d
Reviewed-on: http://gerrit.openafs.org/3945
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementia.org>