wifi: rtw89: add support of concurrent mode

Add iface_combination declaration to enable concurrent mode. Only two
interfaces under same frequency is supported currently. We limit the
role combination to be STA + P2P or STA + AP only for now until new
feature is requested.

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/20230415035016.15788-2-pkshih@realtek.com