Bluetooth: Host: conn_change signal object not correclty initialied

The problem is visible after call to bt_disable when there was
a connection. On a next bt_enable call when hc_tx_thread starts
it is possible that the conn_change object internals are not
re-initialized entirely and the function fails during k_poll call.

The commit changes explicit assignment conn_change object to
a k_poll_signal_init that does proper initialization.

Signed-off-by: Piotr Pryga <[email protected]>

Author: ppryga-nordic

subsys/bluetooth/host/conn.c

@@ -723,7 +723,8 @@ int bt_conn_prepare_events(struct k_poll_event events[])
 
 	BT_DBG("");
 
-	conn_change.signaled = 0U;
+	k_poll_signal_init(&conn_change);
+
 	k_poll_event_init(&events[ev_count++], K_POLL_TYPE_SIGNAL,
 			  K_POLL_MODE_NOTIFY_ONLY, &conn_change);