bwn_plcp_getcck
static uint8_t bwn_plcp_getcck(const uint8_t);
offset += (bwn_plcp_getcck(rate) & 0x000f) * 2;
bwn_plcp_getcck(rate);
txhdr->phyrate_rts = bwn_plcp_getcck(rts_rate);
raw[0] = bwn_plcp_getcck(rate);