wifi: rtw89: process regulatory for 6 GHz power type

Configure the corresponding power type for 6 GHz regulatory if we can
determine one single target. Otherwise, we use the default one.

Signed-off-by: Zong-Zhe Yang <kevin_yang@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/20230602150556.36777-5-pkshih@realtek.com