tests: Fix the stats unit test.

This has been broken since February. The interface for opening
initializing where the stats output should go was changed, but the
test wasn't updated.

Change-Id: I54bd8be15bf870352d5fcfad95ded28d87c7cc5a
Reviewed-on: https://gem5-review.googlesource.com/6001
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
diff --git a/src/unittest/stattestmain.py b/src/unittest/stattestmain.py
index 70fef59..60b041c 100644
--- a/src/unittest/stattestmain.py
+++ b/src/unittest/stattestmain.py
@@ -6,7 +6,7 @@
 
     # Initialize the global statistics
     m5.stats.initSimStats()
-    m5.stats.initText("cout")
+    m5.stats.addStatVisitor("cout")
 
     # We're done registering statistics.  Enable the stats package now.
     m5.stats.enable()