rtw89: declare AP mode support

Things are ready for AP mode, so declare this driver can support it.

Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20220207063900.43643-8-pkshih@realtek.com