rtw88: fix hw scan may cause disconnect issue

After scan aborts we still receive some hw scan c2h packets, and
processing these c2h commands will change current channel. If device
already connect to other AP, driver will set wrong op channel due
to current channel changed. The disconnection happens when hw scan back
to wrong op channel that device can't receive beacon from AP. To fix
this issue, we ignore the late c2h if we are not scanning, and set
current channel back to op channel after scan to align the FW behavior.

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/20220428020521.8015-3-pkshih@realtek.com