cosmetic: rename gsm_subscriber_connection->conn_fsm to ->fi

Match osmo-bsc's naming of the subscriber connection's FSM instance; 'conn->fi'
makes more sense anyway than 'conn->conn_fsm'.

BTW, an upcoming commit will do away with the legacy from libbsc/libmsc duality
and firmly glue the conn allocation to the fi.

Related: OS#3122
Change-Id: If442f2ba78d9722b1065ec30c9a13f372b6a8caa
diff --git a/tests/msc_vlr/msc_vlr_test_authen_reuse.c b/tests/msc_vlr/msc_vlr_test_authen_reuse.c
index 6fd1e66..c9a9d09 100644
--- a/tests/msc_vlr/msc_vlr_test_authen_reuse.c
+++ b/tests/msc_vlr/msc_vlr_test_authen_reuse.c
@@ -166,7 +166,7 @@
 			     "03575886" /* classmark 2 */
 			     "089910070000106005" /* IMSI */);
 		OSMO_ASSERT(g_conn);
-		OSMO_ASSERT(g_conn->conn_fsm);
+		OSMO_ASSERT(g_conn->fi);
 		OSMO_ASSERT(g_conn->vsub);
 		VERBOSE_ASSERT(cm_service_result_sent, == RES_NONE, "%d");
 		VERBOSE_ASSERT(auth_request_sent, == true, "%d");
@@ -217,7 +217,7 @@
 			     "03575886" /* classmark 2 */
 			     "089910070000106005" /* IMSI */);
 		OSMO_ASSERT(g_conn);
-		OSMO_ASSERT(g_conn->conn_fsm);
+		OSMO_ASSERT(g_conn->fi);
 		OSMO_ASSERT(g_conn->vsub);
 		VERBOSE_ASSERT(cm_service_result_sent, == RES_NONE, "%d");
 		VERBOSE_ASSERT(auth_request_sent, == false, "%d");