Bluetooth: Fix Deadlock on Legacy Scan/Pair

Fix nested calls to hci_dev_lock().

Signed-off-by: Brian Gix <bgix@codeaurora.org>
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 1e59cb3..2276428 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -3088,12 +3088,16 @@
 	num_reports = skb->data[0];
 	ev = (void *) &skb->data[1];
 
+	hci_dev_lock(hdev);
+
 	while (num_reports--) {
 		mgmt_device_found(hdev->id, &ev->bdaddr, ev->bdaddr_type,
 				1, NULL, 0, ev->length, ev->data);
 		hci_add_adv_entry(hdev, ev);
 		ev = (void *) (ev->data + ev->length + 1);
 	}
+
+	hci_dev_unlock(hdev);
 }
 
 static inline void hci_le_meta_evt(struct hci_dev *hdev, struct sk_buff *skb)