Cleanup /lib/modules volume mounts in containers

"/lib/modules" volume mount has been introduced for the following
reason:
- "ebtables" in case of neutron-linuxbridge-agent container
- "ipsec" in case of neutron-vpnaas-agent container
- "openvswitch" in case of openvswitch-vswitchd container

For all other containers this is not required and must be removed.

Change-Id: I11610c060f05d2c993394adabd15aa080de3bc24