Have upload_prebuilts respect the debug flag.

bin/cbuildbot.py

Index: bin/cbuildbot.py
diff --git a/bin/cbuildbot.py b/bin/cbuildbot.py
index c75e467cc7fcf9d678734a75887a02ac9b9126cb..2e86ae417356afa7548e70b67a92dadb01299759 100755
--- a/bin/cbuildbot.py
+++ b/bin/cbuildbot.py
@@ -701,8 +701,9 @@ def main():
       if buildconfig['master']:
         # Master bot needs to check if the other slaves completed.
         if cbuildbot_comm.HaveSlavesCompleted(config):
-          _UploadPrebuilts(buildroot, board, buildconfig['rev_overlays'],
-                           [new_binhost])
+          if not options.debug:
+            _UploadPrebuilts(buildroot, board, buildconfig['rev_overlays'],
+                             [new_binhost])
           _UprevPush(buildroot, tracking_branch, buildconfig['board'],
                      push_overlays, options.debug)
         else: