Fix a few coverity unitinitialzed-value warnings in the unit tests.

Coverity can't see that it is not in fact going to read
uninitialized memory here, so we initialize these values
unconditionally.

Bugfix on 0.4.0.1-alpha.

src/test/test_btrack.c

@@ -44,6 +44,8 @@ test_btrack_launch(void *arg)
 {
   orconn_state_msg_t conn;
   ocirc_chan_msg_t circ;
+  memset(&conn, 0, sizeof(conn));
+  memset(&circ, 0, sizeof(circ));
 
   (void)arg;
   conn.gid = 1;
@@ -93,6 +95,8 @@ test_btrack_delete(void *arg)
 {
   orconn_state_msg_t state;
   orconn_status_msg_t status;
+  memset(&state, 0, sizeof(state));
+  memset(&status, 0, sizeof(status));
 
   (void)arg;
   state.gid = 1;

src/test/test_controller_events.c

@@ -429,6 +429,7 @@ static void
 test_cntev_orconn_state(void *arg)
 {
   orconn_state_msg_t conn;
+  memset(&conn, 0, sizeof(conn));
 
   (void)arg;
   MOCK(queue_control_event_string, mock_queue_control_event_string);
@@ -468,6 +469,7 @@ static void
 test_cntev_orconn_state_pt(void *arg)
 {
   orconn_state_msg_t conn;
+  memset(&conn, 0, sizeof(conn));
 
   (void)arg;
   MOCK(queue_control_event_string, mock_queue_control_event_string);
@@ -503,6 +505,7 @@ static void
 test_cntev_orconn_state_proxy(void *arg)
 {
   orconn_state_msg_t conn;
+  memset(&conn, 0, sizeof(conn));
 
   (void)arg;
   MOCK(queue_control_event_string, mock_queue_control_event_string);