md4_vector(), md5_vector(), sha1_vector(), and sha256_vector() already
supported TEST_FAIL() with the OpenSSL crypto implementation, but the
same test functionality is needed for the internal crypto implementation
as well.
Signed-off-by: Jouni Malinen <j@w1.fi>
Some crypto libraries can return in these functions (e.g., if a specific
hash function is disabled), so we better provide the caller a chance to
check whether the call failed. The return values are not yet used
anywhere, but they will be needed for future changes.
