gbproxy: Add test program to test gbproxy message handling

This program tests the gbproxy implementation by passing NS messages
to a modified gbproxy that dumps the resulting messages, signals, and
state.

It focusses on testing abnormal situations like port changes.

Ticket: OW#874
Sponsored-by: On-Waves ehf
diff --git a/openbsc/tests/Makefile.am b/openbsc/tests/Makefile.am
index ed21fc3..7f51bfa 100644
--- a/openbsc/tests/Makefile.am
+++ b/openbsc/tests/Makefile.am
@@ -1,4 +1,4 @@
-SUBDIRS = gsm0408 db channel mgcp gprs si abis
+SUBDIRS = gsm0408 db channel mgcp gprs si abis gbproxy
 
 if BUILD_NAT
 SUBDIRS += bsc-nat bsc-nat-trie