typo fix

Change-Id: I3ff81d18ed436e60c826f45198cfd2739a9a8b0f
diff --git a/drivers/CiscoSX300.py b/drivers/CiscoSX300.py
index 69f707a..dec39f6 100644
--- a/drivers/CiscoSX300.py
+++ b/drivers/CiscoSX300.py
@@ -437,7 +437,7 @@
             except (pexect.EOF, pexect.TIMEOUT):
                 # Something went wrong; logout, log in and try again!
                 print "PEXPECT FAILURE, RECONNECT"
-                raise PExpectError("_cli failed on %s", % text)
+                raise PExpectError("_cli failed on %s" % text)
             except:
                 print "Unexpected error:", sys.exc_info()[0]
                 raise