Add iptables runonce script

- Docker doesn't play nicely with nf_tables. Add a runonce script to use
update-alternatives to enable iptables-legacy. If at some point Docker
works right with nf_tables, we can get rid of this.

b/142268644

Change-Id: Ic38b51fb87d5251be66a6750b673b615e6dc9cee
1 file changed
tree: 1796a3abc17a062cee16aba24956fd2258cfd8d8
  1. debian/
  2. etc/
  3. usr/