compute_crc8
sec_layout.headercrc8 = compute_crc8(crcbuf, bufsize +
sec_layout->headercrc8 = compute_crc8(buffer, sec_layout->headerlength);
calc_crc8 = compute_crc8(bytes, length);
unsigned char compute_crc8(unsigned char *bytes, int length);
unsigned char compute_crc8(unsigned char *bytes, int length);
calc_crc8 = compute_crc8(bytes, length);