rtw88: coex: add write scoreboard action when WLAN in critical procedure

When WLAN in critical procedure, such as connecting, scan and so on,
coexistence will notify BT by scoreboard.
While BT firmware received the scoreboard interrupt, it will adjust
BT page priority lower to avoid WLAN critical procedure suffering impact.

Signed-off-by: Ching-Te Ku <ku920601@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20201112031430.4846-4-pkshih@realtek.com