pdevs/mpi: add debug info

src/tests/mpi/cluster/main.cpp

@@ -203,6 +203,8 @@ void example_simple(int argc, char *argv[])
 
         steady_clock::time_point t1 = steady_clock::now();
 
+	std::cout << "START" << std::endl;
+	
         rc.run();
 
         steady_clock::time_point t2 = steady_clock::now();