Set maxDiff to None in the debug decorator. NFC

This makes it possible for us to see large diffs between the actual and
expected values when debugging a test.

Change-Id: Iad81fb4c3b3a3306f3ad2ce842c47363e302cb5f
diff --git a/tests/cli/llvmtestcase.py b/tests/cli/llvmtestcase.py
index db3635f..0f29ce6 100644
--- a/tests/cli/llvmtestcase.py
+++ b/tests/cli/llvmtestcase.py
@@ -21,6 +21,9 @@
     def wrapper(*args, **kwargs):
         # Catch any exceptions so we can dump all the output
         try:
+            self = args[0]
+            self.maxDiff = None # So we can see large diffs between
+                                # expected/actual
             test(*args, **kwargs)
         except subprocess.CalledProcessError as exc:
             print("Error in {}:".format(test.__name__))