wifi: rtw88: add bitmap for dynamic port settings

In order to support multiple interfaces, multiple port settings will
be required. Current code always uses port 0 and should be changed.
Declare a bitmap with size equal to hardware port number to record
the current usage.

Signed-off-by: Po-Hao Huang <phhuang@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/20230414121135.17828-2-pkshih@realtek.com