Remove bridge from nic1 in network bond templates

Remove bridge from nic1 in network bond templates

The bridge that is built on the bonds in the bond-with-vlans
example has an extraneous bridge on the storage and compute
templates, and an incorrect bridge on the controller template.
There is no reason to do anything on nic1, which is assumed to
be the provisioning interface, because it will be configured by
DHCP. Also, on the controller template we actually want br-ex
to contain the VLAN with the external network, rather than be
configured on the provisioning interface.

Change-Id: Ibe2343d5281f7b63a7b63b17d96d8442d0b96105