This makes sure that once we have ro rootfs any programs that still
for any reason use `/tmp` can still write to it, or if people expect
sharing it into a container to work.
fix#778
Signed-off-by: Justin Cormack <justin.cormack@docker.com>
This is needed for volume drivers as they will mount their
volumes under here, and if they are running in a container
docker on the host will need to see these.
Also provide our own fstab, removes the media devices that were
there previously.
Signed-off-by: Justin Cormack <justin.cormack@docker.com>
