update hooks: clean old module packages

Some people have these old packages lying around, so clear them out
automatically so people don't have to manually recover.

BUG=chromium:396816
TEST=`./update_chroot` worked

Change-Id: Ida45e910fc1709790f4af65ed5b8d47f134022de
Reviewed-on: https://chromium-review.googlesource.com/210440
Reviewed-by: Steve Fung <stevefung@chromium.org>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
1 file changed