qcacmn: Return success during the sched stop request

In a scenario wherein after the sched_scan_start there is a system
recovery and previous pending sched_scan request is lost and during
the sched_scan_stop driver is returning error.
Because of which __cfg80211_stop_sched_scan will not
clear “rdev->sched_scan_req” blocking further sched_scan requests.

Return success in the event that the driver does not have any pending
sched scan to flush.

Change-Id: I6aba88ce033c59ebae54ca792e241a17b649ad73
CRs-Fixed: 2340653

os_if/linux/scan/src/wlan_cfg80211_scan.c

@@ -587,27 +587,31 @@ error:
 int wlan_cfg80211_sched_scan_stop(struct wlan_objmgr_pdev *pdev,
 	struct net_device *dev)
 {
-	int ret = 0;
 	QDF_STATUS status;
 	struct wlan_objmgr_vdev *vdev;
 
 	vdev = wlan_objmgr_get_vdev_by_macaddr_from_pdev(pdev, dev->dev_addr,
 		WLAN_OSIF_ID);
 	if (!vdev) {
+	/*
+	 * cfg80211 expects sched_scan_stop command to always succeed.
+	 * There can be recovery or any other error in the driver between the
+	 * sched_scan_start and sched_scan_stop commands. If driver does
+	 * not return success in this case there is a possibility of further
+	 * sched_scan_start request might not be received again.
+	 */
 		cfg80211_err("vdev object is NULL");
-		return -EIO;
+		return 0;
 	}
 
 	status = ucfg_scan_pno_stop(vdev);
-	if (QDF_IS_STATUS_ERROR(status)) {
+	if (QDF_IS_STATUS_ERROR(status))
 		cfg80211_err("Failed to disabled PNO");
-		ret = -EINVAL;
-	} else {
+	else
 		cfg80211_info("PNO scan disabled");
-	}
 
 	wlan_objmgr_vdev_release_ref(vdev, WLAN_OSIF_ID);
-	return ret;
+	return 0;
 }
 #endif /*FEATURE_WLAN_SCAN_PNO */