Bluetooth: btqcomsmd: Fix skb double free corruption

In case of hci send frame failure, skb is still owned
by the caller (hci_core) and then should not be freed.

This fixes crash on dragonboard-410c when sending SCO
packet. skb is freed by both btqcomsmd and hci_core.

Fixes: 1511cc75 ("Bluetooth: Introduce Qualcomm WCNSS SMD based HCI driver")
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

drivers/bluetooth/btqcomsmd.c

@@ -88,7 +88,8 @@ static int btqcomsmd_send(struct hci_dev *hdev, struct sk_buff *skb)
 		break;
 	}
 
-	kfree_skb(skb);
+	if (!ret)
+		kfree_skb(skb);
 
 	return ret;
 }