wifi: rtw88: fix stopping queues in wrong timing when HW scan

HW scan need to start queues after switch to OP channel, and stop queues
before leaving op channel. However, in original code, driver will start
queues after switch to OP channel, but stop queues until switch to OP
channel next time, that will cause packets transmitted in wrong channel.
So we fix the stop queues timing.

Signed-off-by: Chih-Kang Chang <gary.chang@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/20220727065003.28340-3-pkshih@realtek.com