rtw89: add new state to CFO state machine for UL-OFDMA

Add an new state, RTW89_PHY_DCFO_STATE_HOLD, to keep CFO acceleration
after CFO_PERIOD_CNT if the traffic is UL-OFDMA, which is calculated
based on RX trigger frame counter.

Signed-off-by: Eric Huang <echuang@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20220608113224.11193-4-pkshih@realtek.com