rtw89: 8852a: add ieee80211_ops::hw_scan

Declare this function allows us to use customized scanning policy, so
each scan takes less time. This is a similar implementation to hw_scan
in rtw88, except that we offload more items to firmware and extend the
maximum IE length. For backward compatibility, we fallback to sw_scan
when firmware does not support this feature.

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/20220225030851.13327-2-pkshih@realtek.com