tweak octal numbers style to work with python-3

BUG=None
TEST=`./run_tests` passed

Change-Id: Ife102f80efdb5e040dc2ba96ac7aa4ee3f7a6c75
Reviewed-on: https://chromium-review.googlesource.com/173729
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
diff --git a/scripts/upload_prebuilts.py b/scripts/upload_prebuilts.py
index 5a1c94c..806f51b 100644
--- a/scripts/upload_prebuilts.py
+++ b/scripts/upload_prebuilts.py
@@ -723,7 +723,7 @@
 
 def main(_argv):
   # Set umask to a sane value so that files created as root are readable.
-  os.umask(022)
+  os.umask(0o22)
 
   options, target = ParseOptions()