Add in an x86-alex_nogobi configuration for cbuildbot in R12

BUG=chrome-os-partner:4440
TEST=NA
diff --git a/buildbot/cbuildbot_config.py b/buildbot/cbuildbot_config.py
index ac9f8c4..eccdf5a 100644
--- a/buildbot/cbuildbot_config.py
+++ b/buildbot/cbuildbot_config.py
@@ -168,6 +168,18 @@
   'git_url' : 'ssh://gerrit-int.chromium.org:29419/chromeos/manifest-internal',
 })
 
+config['x86-alex_nogobi-pre-flight-branch'] = default.copy()
+config['x86-alex_nogobi-pre-flight-branch'].update({
+  'board' : 'x86-alex_nogobi',
+  'master' : False,
+
+  'uprev' : True,
+  'rev_overlays': 'both',
+  'push_overlays': None,
+  'git_url' : 'ssh://gerrit-int.chromium.org:29419/chromeos/manifest-internal',
+})
+
+
 config['x86-mario-pre-flight-branch'] = default.copy()
 config['x86-mario-pre-flight-branch'].update({
   'board' : 'x86-mario',