Don't print the list of configs if one is misspecfied.

The list of targets has become so long that it takes a lot of time to
scroll up to find which target you mistyped when running multiple trybots.
This CL removes the dumping of the list and instead instructs the caller
to run cbuildbot --list --all themself.

BUG=None
TEST=Pylint / pyflakes / unittest + ran with invalid config.

Change-Id: I6f42d3a76c1ed4088729cbf854066d6fcbbeb502
Reviewed-on: https://chromium-review.googlesource.com/195243
Tested-by: Chris Sosa <sosa@chromium.org>
Reviewed-by: Yu-Ju Hong <yjhong@chromium.org>
Reviewed-by: David James <davidjames@chromium.org>
Commit-Queue: Chris Sosa <sosa@chromium.org>
diff --git a/scripts/cbuildbot.py b/scripts/cbuildbot.py
index 17272fd..9494dee 100644
--- a/scripts/cbuildbot.py
+++ b/scripts/cbuildbot.py
@@ -1485,13 +1485,13 @@
                          % default)
 
   # Ensure that all args are legitimate config targets.
-  invalid_target = False
+  invalid_targets = []
   for arg in args:
     build_config = _GetConfig(arg)
 
     if not build_config:
+      invalid_targets.append(arg)
       cros_build_lib.Error('No such configuraton target: "%s".', arg)
-      invalid_target = True
       continue
 
     if options.channels and build_config.build_type != constants.PAYLOADS_TYPE:
@@ -1508,10 +1508,10 @@
       cros_build_lib.Die('Cannot specify --version without --buildbot for an'
                          ' external target (%s).' % arg)
 
-  if invalid_target:
-    print 'Please specify one of:'
-    _PrintValidConfigs()
-    cros_build_lib.Die('One or more invalid configuration targets specified.')
+  if invalid_targets:
+    cros_build_lib.Die('One or more invalid configuration targets specified. '
+                       'You can check the available configs by running '
+                       '`cbuildbot --list --all`')
 
 
 def _ParseCommandLine(parser, argv):