If we're complaining about multiple build configs, output the args.

BUG=None
TEST=cbuildbot {x86-generic,mario}-paladin

Change-Id: I0337ad57cdcc6a3fa3002361b2a6bdb38e562ee5
Reviewed-on: https://gerrit.chromium.org/gerrit/27772
Commit-Ready: Brian Harring <ferringb@chromium.org>
Tested-by: Brian Harring <ferringb@chromium.org>
Reviewed-by: David James <davidjames@chromium.org>
diff --git a/scripts/cbuildbot.py b/scripts/cbuildbot.py
index f112b72..5e755c2 100644
--- a/scripts/cbuildbot.py
+++ b/scripts/cbuildbot.py
@@ -1004,7 +1004,7 @@
   else:
     if len(args) > 1:
       cros_build_lib.Die('Multiple configs not supported if not running with '
-                         '--remote.')
+                         '--remote.  Got %r', args)
 
     if options.slaves:
       cros_build_lib.Die('Cannot use --slaves if not running with --remote.')