* \brief noekeon encrytion funtion
*
* This function decrypts a block (64 bit = 8 byte) encrypted with the noekeon
* encrytion algorithm. Due to the two modes of noekeon (direct mode and
* indirect mode) the second parameter either points directly to the key
* (direct mode) or to a context generated by the noekeon_init() function
* \brief noekeon encrytion funtion
*
* This function decrypts a block (64 bit = 8 byte) encrypted with the noekeon
* encrytion algorithm. Due to the two modes of noekeon (direct mode and
* indirect mode) the second parameter either points directly to the key
* (direct mode) or to a context generated by the noekeon_init() function