Bluetooth: Update background scanning from hci_conn_params_clear

When calling hci_conn_params_clear function, it should update the
background scanning properly and not require a separate call to
update it.

For the case when the function is used during unregister of a
controller, an extra safe guard is but in place.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

net/bluetooth/hci_core.c

@@ -959,7 +959,6 @@ static ssize_t le_auto_conn_write(struct file *file, const char __user *data,
 	} else if (memcmp(buf, "clr", 3) == 0) {
 		hci_dev_lock(hdev);
 		hci_conn_params_clear(hdev);
-		hci_update_background_scan(hdev);
 		hci_dev_unlock(hdev);
 	} else {
 		err = -EINVAL;
@@ -3483,6 +3482,8 @@ void hci_pend_le_conns_clear(struct hci_dev *hdev)
 	}
 
 	BT_DBG("All LE pending connections cleared");
+
+	hci_update_background_scan(hdev);
 }
 
 /* This function requires the caller holds hdev->lock */
@@ -5293,6 +5294,9 @@ void hci_update_background_scan(struct hci_dev *hdev)
 	struct hci_conn *conn;
 	int err;
 
+	if (test_bit(HCI_UNREGISTER, &hdev->dev_flags))
+		return;
+
 	hci_req_init(&req, hdev);
 
 	if (list_empty(&hdev->pend_le_conns)) {