=== Split osmo-gbproxy from osmo-sgsn ===

Adjust the build system, packaging etc. to split osmo-gbproxy into its
own git repository. Remove tests and configs that aren't related to
osmo-gbproxy.

Related: OS#4992
diff --git a/src/gb_proxy_peer.c b/src/gb_proxy_peer.c
index 7d6ba86..e276c85 100644
--- a/src/gb_proxy_peer.c
+++ b/src/gb_proxy_peer.c
@@ -22,7 +22,7 @@
 
 #include <osmocom/sgsn/gb_proxy.h>
 
-#include <osmocom/sgsn/debug.h>
+#include "debug.h"
 
 #include <osmocom/gprs/protocol/gsm_08_18.h>
 #include <osmocom/core/crc16.h>