Fix cloud-init routing issue on Fedora

Add "NONZEROCONF=yes" to /etc/sysconfig/network to prevent
169.254.0.0 route from being created. This route interferes
with fedora baremetal nodes' access to the nova metadata
server at 169.254.169.254.

Change-Id: Iad77abfc97c0eba944680772f233389481a270ff