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.
diff --git a/openbsc/tests/bsc-nat/prefixes.csv b/openbsc/tests/bsc-nat/prefixes.csv
index 0b66ffe..0c7660f 100644
--- a/openbsc/tests/bsc-nat/prefixes.csv
+++ b/openbsc/tests/bsc-nat/prefixes.csv
@@ -1 +1,2 @@
0172,0049
++49,0