staging: wfx: unlock on error path

We need to release the tx_lock on the error path before returning.

Fixes: d1c015b4 ("staging: wfx: rewrite wfx_hw_scan()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20200512083656.GA251760@mwandaSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/wfx/scan.c

@@ -57,8 +57,10 @@ static int send_scan_req(struct wfx_vif *wvif,
 	wvif->scan_abort = false;
 	reinit_completion(&wvif->scan_complete);
 	timeout = hif_scan(wvif, req, start_idx, i - start_idx);
-	if (timeout < 0)
+	if (timeout < 0) {
+		wfx_tx_unlock(wvif->wdev);
 		return timeout;
+	}
 	ret = wait_for_completion_timeout(&wvif->scan_complete, timeout);
 	if (req->channels[start_idx]->max_power != wvif->vif->bss_conf.txpower)
 		hif_set_output_power(wvif, wvif->vif->bss_conf.txpower);