RATE_9M_IDX
{-87, RATE_9M_IDX},
next_rate = RATE_9M_IDX;
if (idx >= RATE_9M_IDX)
RATE_6M_IDX, RATE_9M_IDX,
if (mac_idx >= (RATE_9M_IDX - IL_FIRST_OFDM_RATE))
#define RATE_9M_MASK (1 << RATE_9M_IDX)