buffet: Pass --enable_xmpp flag through init script

BUG=brillo:769
TEST=Running buffet_Registration against buffet with this code
     yields log messages about XMPP being disabled by flag.

Change-Id: I21e618025e2f79a8557780db4d30ed3d5818dd37
Reviewed-on: https://chromium-review.googlesource.com/265761
Tested-by: Christopher Wiley <wiley@chromium.org>
Reviewed-by: Alex Vakulenko <avakulenko@chromium.org>
Commit-Queue: Alex Vakulenko <avakulenko@chromium.org>
1 file changed
tree: 939e6e8187f25429bd699af28e496f306d3baa16
  1. buffet/