Enforce formatting of bp files on repo upload

Test: modified an incorrectly formatted .bp file and attempted to
      upload just to make sure it was rejected.
Change-Id: Ib51cedb8b24d61c416a53a447a909314cc0e91c3
diff --git a/PREUPLOAD.cfg b/PREUPLOAD.cfg
index 2fd2e33..33fd399 100644
--- a/PREUPLOAD.cfg
+++ b/PREUPLOAD.cfg
@@ -1,5 +1,6 @@
 [Builtin Hooks]
 clang_format = true
+bpfmt = true
 
 [Builtin Hooks Options]
 # Only turn on clang-format check for the following subfolders.