test_ndnpeekpoke: don't delete logs during tear down

refs #3060

Change-Id: I6cd71429ac511041fbce273a3ba5b8b0968dd679
diff --git a/test_ndnpeekpoke/test_ndnpeekpoke.py b/test_ndnpeekpoke/test_ndnpeekpoke.py
index 7b2325e..9f218e9 100644
--- a/test_ndnpeekpoke/test_ndnpeekpoke.py
+++ b/test_ndnpeekpoke/test_ndnpeekpoke.py
@@ -17,13 +17,12 @@
     def setUp(self):
         print "\nTesting ndnpeek & ndnpoke"
         print "***********************************"
-        os.system("mkdir test_ndnpeekpoke/logs/")
+        os.system("mkdir -p test_ndnpeekpoke/logs/")
 
     def tearDown(self):
         self.killNfd()
         self.killProcess("ndnpoke")
         self.killProcess("ndnpeek")
-        os.system("rm -r test_ndnpeekpoke/logs/")
         self.cleanupProcesses()
 
     def test_peekpoke(self):