Bluetooth: Enhance error codes pair device command

If user space is trying to pair on not enabled transport
MGMT_STATUS_REJECT will be returned.

If user space is trying to pair on transport which controller does not
support, MGMT_STATUS_NOT_SUPPORTED will be returned.

Having separate error code for that scenario might be useful for
debugging at least.
Signed-off-by: NLukasz Rymanowski <lukasz.rymanowski@tieto.com>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

net/bluetooth/mgmt.c

@@ -3249,6 +3249,10 @@ static int pair_device(struct sock *sk, struct hci_dev *hdev, void *data,
 
 		if (PTR_ERR(conn) == -EBUSY)
 			status = MGMT_STATUS_BUSY;
+		else if (PTR_ERR(conn) == -EOPNOTSUPP)
+			status = MGMT_STATUS_NOT_SUPPORTED;
+		else if (PTR_ERR(conn) == -ECONNREFUSED)
+			status = MGMT_STATUS_REJECTED;
 		else
 			status = MGMT_STATUS_CONNECT_FAILED;