nat: Implement a post-routing for the NAT software

* The post-routing is applied after the first re-writing. To do this
  the new number is copied back into the called data structure.

* Add a testcase that goes from 0172 to 0049 and then back to 0049
  using the post rule with a table lookup.
7 files changed
tree: 20c5541ac8327dcf27a05717485d47216d2d46a2
  1. debian/
  2. hlrsync/
  3. linux-kernel/
  4. openbsc/
  5. wireshark/
  6. README