nat: Make queue_for_msc use the msc_con parameter, pass in the right msc_con

* Return msg'es to the right MSC Con. Right now it is nat->msc_con.
* When forwarding from BSC to MSC, use the msc_con inside the
  sccp_connections. This means we will only forward data with a
  connection to the BSC.
1 file changed
tree: 907742b7f2c74c9b3907821b9a3114bca5ea43a8
  1. hlrsync/
  2. linux-kernel/
  3. openbsc/
  4. wireshark/