rtw89: ser: re-enable interrupt in threadfn if under_recovery

Normally, we re-enable interrupt by napi_poll, but for this special
situation, we must turn it on immediately because napi_poll isn't
scheduled.

Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20220421120903.73715-6-pkshih@realtek.com