use cd to resolve *'s properly in packaging/linux/deb/layout_repo.sh
use cd to resolve *'s properly in packaging/linux/deb/layout_repo.sh

I'm actually not sure how this worked before. Without cd'ing to the
directory where the links are going to be, the local path doesn't refer
to any existing files, and the * won't expand. This broke today's Debian
release, and I had to fix the result manually in server-ops.

keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client