rtw89: 8852c: disable firmware watchdog if CPU disabled

Disable watchdog timer to prevent it timeout suddenly.

Signed-off-by: Chia-Yuan Li <leo.li@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/20220408001353.17188-8-pkshih@realtek.com