aoip: add osmo-stp, now required for aoip runs

Change-Id: I35d4cb0d173eec240bccc1f3a5965a774b7b3506
diff --git a/suites/aoip_debug/interactive.py b/suites/aoip_debug/interactive.py
index cfedd3a..d596b68 100755
--- a/suites/aoip_debug/interactive.py
+++ b/suites/aoip_debug/interactive.py
@@ -5,9 +5,11 @@
 mgcpgw = suite.mgcpgw(bts_ip=bts.remote_addr())
 msc = suite.msc(hlr, mgcpgw)
 bsc = suite.bsc(msc)
+stp = suite.stp()
 modems = suite.modems(int(prompt('How many modems?')))
 
 hlr.start()
+stp.start()
 msc.start()
 mgcpgw.start()