Split call control from built-in call console by using MNCC layer

src/test/dummy.c

@@ -1,8 +1,8 @@
-void call_rx_audio() { }
-void call_out_setup() { }
-void call_out_release() { }
-void call_out_disconnect() { }
-void call_out_answer() { }
+void call_down_audio() { }
+void call_down_setup() { }
+void call_down_release() { }
+void call_down_disconnect() { }
+void call_down_answer() { }
 void print_help() { }
 void sender_send() { }
 void sender_receive() { }