Create a "ms_driver" stub for the testsuite

All config parameters are hardcoded for now and it should push
subscribers into the test (which should be a base class but not
a specific test).

Change-Id: I586b6d532c6e6395b4e6f2cf2128372237d05a7d
diff --git a/src/osmo_gsm_tester/suite.py b/src/osmo_gsm_tester/suite.py
index 932a6ab..22a47a2 100644
--- a/src/osmo_gsm_tester/suite.py
+++ b/src/osmo_gsm_tester/suite.py
@@ -23,7 +23,7 @@
 import pprint
 from . import config, log, util, resource, test
 from .event_loop import MainLoop
-from . import osmo_nitb, osmo_hlr, osmo_mgcpgw, osmo_mgw, osmo_msc, osmo_bsc, osmo_stp, osmo_ggsn, osmo_sgsn, modem, esme, osmocon
+from . import osmo_nitb, osmo_hlr, osmo_mgcpgw, osmo_mgw, osmo_msc, osmo_bsc, osmo_stp, osmo_ggsn, osmo_sgsn, modem, esme, osmocon, ms_driver
 
 class Timeout(Exception):
     pass
@@ -311,6 +311,11 @@
             ip_address = self.ip_address()
         return osmo_stp.OsmoStp(self, ip_address)
 
+    def ms_driver(self):
+        ms = ms_driver.MsDriver(self)
+        self.register_for_cleanup(ms)
+        return ms
+
     def bts(self, specifics=None):
         bts = bts_obj(self, self.reserved_resources.get(resource.R_BTS, specifics=specifics))
         bts.set_lac(self.lac())