[utils/FuzzTest] The help message says that if you don't specify --max-tests
"the script will run forever continually picking new tests to run", make it so.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@152327 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/FuzzTest b/utils/FuzzTest
index 2b02bc1..b962eb0 100755
--- a/utils/FuzzTest
+++ b/utils/FuzzTest
@@ -250,7 +250,7 @@
     group.add_option("", "--test", help="Run a particular test",
                      type=int, dest="test", default=None, metavar="INDEX")
     group.add_option("", "--max-tests", help="Maximum number of tests",
-                     type=int, dest="max_tests", default=10, metavar="COUNT")
+                     type=int, dest="max_tests", default=None, metavar="COUNT")
     group.add_option("", "--pick-input",
                      help="Randomly select an input byte as well as fuzzing",
                      action='store_true', dest="pick_input", default=False)