CCM Authentication optimization

CCM   is now optimized. Instead of being computed twice,
libtomcrypt code has been optimized so that classical ccm_init, ccm_process,...
can be used incrementally (when the whole stream is not available when
starting the authentication).
CCM way of proceeding is now very closed to GCM authentication.
ccm_add_nonce() doesn't return an error if nonce_len is too large, it just uses the largest supported value if that's good enough for compliance then we should remove the check above at lines 101-102.