=== 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/include/osmocom/Makefile.am b/include/osmocom/Makefile.am
new file mode 100644
index 0000000..09db97a
--- /dev/null
+++ b/include/osmocom/Makefile.am
@@ -0,0 +1,3 @@
+SUBDIRS = \
+	sgsn \
+	$(NULL)