rtw89: 8852c: add write/read crystal function in CFO tracking

The CFO tracking algorithm is the same, but control methods are different.
Set parameters via xtal serial interfaces (SI).

Signed-off-by: Yuan-Han Zhang <yuanhan1020@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/20220317055543.40514-3-pkshih@realtek.com