Modify repo to use http instead of git, some of or slaves cannot communicate over git

Review URL: http://codereview.chromium.org/3173006

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@55778 0039d316-1c4b-4281-b951-d872f2087c98

repo

@@ -2,7 +2,7 @@
 
 ## repo default configuration
 ##
-REPO_URL='git://android.git.kernel.org/tools/repo.git'
+REPO_URL='http://android.git.kernel.org/tools/repo.git'
 REPO_REV='stable'
 
 # Copyright (C) 2008 Google Inc.