systemc: Make a test use cout for all its messages.

This makes them end up in simout so verify.py can find them when it's
checking output.

Change-Id: I2b7b276b3e1816a257f58b0cfb13487d6296e6fd
Reviewed-on: https://gem5-review.googlesource.com/12216
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

src/systemc/tests/systemc/kernel/sc_start/sc_start_0/test1/test1.cpp

@@ -111,7 +111,7 @@ int sc_main(int argc, char* argv[])
 	ACTION(sc_start(0, SC_NS),"sc_start(0, SC_NS)")
 	ACTION(sc_start(0, SC_NS),"sc_start(0, SC_NS)")
 
-    cerr << "Program completed" << endl;
+    cout << "Program completed" << endl;
     return 0;
 }