oap: add oap testsuite skeleton

Sponsored-by: On-Waves ehf
diff --git a/openbsc/tests/oap/oap_test.ok b/openbsc/tests/oap/oap_test.ok
new file mode 100644
index 0000000..e411ad9
--- /dev/null
+++ b/openbsc/tests/oap/oap_test.ok
@@ -0,0 +1,2 @@
+not implemented
+Done